CN102458975A

CN102458975A - Biaxial stern catamaran ship

Info

Publication number: CN102458975A
Application number: CN2010800348753A
Authority: CN
Inventors: 佐佐木纪幸; 平田信行; 藤泽纯一; 岸本雅裕; 辻本胜; 久米健一; 川并康刚; 黑田麻利子; 长谷川纯
Original assignee: National Maritime Research Institute
Current assignee: National Maritime Research Institute
Priority date: 2009-06-06
Filing date: 2010-06-02
Publication date: 2012-05-16
Anticipated expiration: 2030-06-02
Also published as: KR20120028366A; CN103991508B; CN102458975B; CN103991508A; KR101576717B1; WO2010140357A1; KR20130120555A

Abstract

Propulsive performance for a ship is improved by effective use of flows generated in rear of skegs when the ship is propelled. A biaxial stern catamaran ship (1) provided with two propellers is provided with propelling means (210, 220) which propel the biaxial stern catamaran ship by driving the two propellers and the two skegs (11, 12) which are provided at the body of the biaxial stern catamaran ship. The centers of the drive shafts of the two propellers are respectively positioned with offset from the center axes of the two skegs. Each of the skegs is twisted in an S-shape so as to change the flow naturally generated toward the rear of the skegs while the ship sails into a rotational flow, and a lot of the generated rotational flows are caught as a counter flow by the blade surface of the propeller positioned at an optimal position.

Description

Twin shaft stern catamaran oceangoing ship

Technical field

The present invention relates to a kind of twin shaft stern catamaran oceangoing ship (biaxial stern catamaran ship) with two stern fins (skeg) and two screw propellers (propeller).

Background technology

In recent years, increasingly serious along with rising sharply of fuel cost and the energy, environmental problem, also exploring various realization method for saving energy at ship domain.The Infrastructure of locating except the sailing method that is conceived to boats and ships and bay etc. realize energy-conservation, realize that to boats and ships itself method for saving energy has the engine efficiency of raising and improvement ship type.As a ring that improves the ship type, have several the prior aries of studying to propelling unit such as the screw propeller that is positioned at stern and the peripheral ship type of the propelling unit relevant with this propelling unit.

Patent documentation 1 discloses in having the boats and ships of twin skeg, through lateral bending is bent from the Central Line of hull with the bottom of its stern fin, can reduce the resistance of stern fin, the technological thought of the propulsion quality when improving navigation outwardly.

But this technology only is to be conceived to the resistance this point that stern upwelling when changing stern fin-shaped shape and utilize propulsion of ship improves propulsive force and reduce the stern fin consider, does not consider to improve the propulsion coefficient of boats and ships.

Patent documentation 2 discloses following technological thought: in having the boats and ships of twin skeg; Through the fin (fin) of horizontal direction is set about the rear of each stern fin; Wash to the inside and outside both sides at each stern fin produce is carried out rectification; Under the prerequisite of not blocking upwelling, weaken katabatic drainage, thereby reduce the loss of pressure that katabatic drainage causes, can reduce hull resistance thus.

But this technological thought is to carry out the thought that rectification reduces the loss of pressure of hull through the katabatic drainage to wash, does not relate to the propulsion coefficient that improves boats and ships.

Patent documentation 3 discloses following technological thought: a face at the rear portion, side of the installation housing that will vertically be provided with in the angle of rake screw propeller the place ahead that constitutes boats and ships forms court's direction bevelled conical surface identical with the direction of tilt of the blade of screw propeller.Thus; To the screw propeller of avoiding high speed revolution and in its periphery flowing water flow; The formed conical surface in rear portion, side of the installation housing through being arranged on screw propeller the place ahead changes its flow regime; Thereby can send into compressed water towards screw propeller from the reversing sense of the hand of rotation of screw propeller.Through this water of sending into, eliminate the state near idle running of screw propeller, thereby the screw propeller of rotation can increase discharge rate towards the rear, can improve the propulsion coefficient of boats and ships thus, and then can also help to improve consumption of fuel.

But this technology is to conceive for the reduction phenomenon that alleviates the caused propulsion coefficient of current of avoiding screw propeller that (even little by little) produce because of the existence of the installation housing that is positioned at screw propeller the place ahead, is not the propulsion coefficient that really improves boats and ships.

Patent documentation 4 discloses the technological thought of the shortcoming that is used to eliminate high-speed boat.Promptly; With regard to high-speed boat; Propeller blade produces propulsive force in the latter half that is in water one side under many circumstances; And, therefore there is the shortcoming that can not produce enough propulsive forces and can't fully absorb screw propeller rotation counter-force in the face that comprises prop shaft to be the wake flow that the center produces the lower stern fin of flow velocity.Therefore, disclose eccentric installation of face that will comprise prop shaft relatively, improved the technological thought of this shortcoming in view of the above by the thin assembly type stern fin that high strength material is processed.

But patent documentation 4 is being applied in the high-speed boat as prerequisite, considers to the situation that the surface of the first half of screw propeller is positioned on the water surface.Therefore, its technical field and technical matters are different from the present invention who relates to the general purpose hauling purposes boats and ships with stern fin.That is to say, do not consider the influence of shell (housing) downside of axle drive shaft, the measure that the inefficiency phenomenon that neither cause to receiving the roughly housing of half gear case that is in water (casing) influence is taked.And, just with the amount that increases the current of colliding with screw propeller as purpose, therefore can't see it has fully considered the hand of rotation of screw propeller and the contacting mechanism of current, is not the propulsion coefficient that really improves boats and ships.In this, be different from the present invention the purpose and the problem to be solved by this invention that will reach.

Patent documentation 5 illustrates the technological thought of the boats and ships that possess eccentric shaft; These boats and ships have following formation: following the preceding of boats and ships and then on the screw propeller face, producing in the general boats and ships of the vertical whirlpool of the contrary rotation of pair of right and left; Possess the stern contour structures that keeps left-right symmetric property the influence that the configuration except its prop shaft causes and for the right rotation screw propeller from the position configuration centre of gration on hull line of centers deflection right side and for the anticlockwise screw propeller at screw propeller, so that said screw propeller is obtained respectively and the rightabout current of screw propeller hand of rotation in the both sides of said centre of gration by the vertical whirlpool of said pair of right and left from the position configuration centre of gration in hull line of centers deflection left side.

According to patent documentation 5; Under the prerequisite that keeps the roughly symmetrical ship type of hull shape, through making the prop shaft hull line of centers that squints slightly, thereby be utilized in the current that cause vertical whirlpool that propulsion coefficient reduces in the bigger existing ship of beam of hull; Can significantly improve the propulsion coefficient (improving about 10%) of screw propeller on the contrary; And owing to be ship type roughly symmetrical about hull shape, therefore than ship with asymmetric ship type, the low and design easily of laid down cost.

But; This patent documentation 5 is to be applied to screw propeller and then has the existing ship of the quarter of a ship that runs through prop shaft in its place ahead example, is not can be applied to the diverse twin shaft stern of the current catamaran oceangoing ship at stern place or be equipped with the technology on the pod propulsion propelling unit boats and ships of (claiming the POD propelling unit again) therefore.

Patent documentation 6,7 and 8 discloses following technological thought: in the boats and ships with a propelling arbor; In order to improve consumption of fuel through the current that improve relative screw propeller; The a part of stern that advances arbor top is designed to unsymmetric structure; And the bottom combination advancing arbor has the asymmetric ship portion of globoid or U font body and/or the stern part of reversing, and constitutes hull thus.

But; As patent documentation 6,7 and 8 is shown; Advancing arbor is not that relative quarter of a ship divides the generation skew and carries out set positions; And if adopt crooked hull single-piece structure as the means of the current that improve relative screw propeller, then the part that bends of this hull single-piece will produce resistance, become the reason of reduction propulsion coefficient.Therefore, above-mentioned structure may not be an actv. as the means that improve propulsion of ship efficient.

Patent documentation 9 discloses following technological thought: in having boats and ships that advance arbor, on hull, towards the groove of the propeller shape curl of stern, improve the current of relative screw propeller thus.

But as shown in the patent documentation 9, if be employed in the structure that forms spiral groove on the hull as the means of the current that improve relative screw propeller, then this groove branch produces resistance, becomes the reason that reduces propulsion coefficient.Therefore, above-mentioned structure may not be an actv. as the means that improve propulsion of ship efficient.

Patent documentation 10 discloses a kind of catamaran with the fin that reduces to swing; This catamaran possesses the movable fin of the longitudinal oscillation that is used to suppress hull in the rearward end that is formed at the tunnel-like recess between the hull of the left and right sides; For the current that flow into this fin are quickened, the width of said tunnel-like recess is along reducing gradually from the direction of fore part towards the stern part.

But this technological purpose is to reduce the longitudinal oscillation of hull, does not relate to the propulsion coefficient that improves boats and ships.

Patent documentation 11 discloses the technology that relates to the double body type water-jet propelled craft, and this double body type water-jet propelled craft has the pipeline of the water-jet nozzle that extends to aft end by the intake of the bottom surface that is separately positioned on left and right sides hull part on the quarter, from this intake and the hydraulic efficiency jet propulsion system that the impeller in this pipeline constitutes.

But; The intention of this technology is that through the inside part at intake gassing current guiding being set to be pressed into pressurized air through lift fan to air chamber with groove and make hull when the state that rises navigates by water down; Prevent to reveal the intake that gassing current flows into hydraulic efficiency jet propulsion system; Compare with the present invention, technical matters to be solved is different.

Patent documentation 12 discloses the technology that relates to the air pressure support type boats and ships with sidewall; These air pressure support type boats and ships have the catamaran type shape that has a pair of elongate side wall at port and starboard; At least on the bow tail end has the sealing member by the pliability materials for support between two hulls; The air chamber storage high pressure air that is surrounded by fore tail sealing member through at the binary hull supports most of hull weight, and has equipped Embedded waterjet propulsor as its propelling unit.

But; The intention of this technology is the inside face in the two side of binary hull, separates guide plate through lifting mode, need not to reduce air-cushion pressure and hull is descended; Can prevent the intake aspirated air from waterjet propulsor, its technical matters to be solved is different from the present invention.

The prior art document

Patent documentation

Patent documentation 1: TOHKEMY 2007-223557 communique

Patent documentation 2: TOHKEMY 2006-341640 communique

Patent documentation 3: Japanese Utility Model is logined communique No. 2604037

Patent documentation 4: US Pat the 6th, 155, No. 894 specification sheetss

Patent documentation 5: the special fair 04-046799 communique of Japan

Patent documentation 6: japanese kokai publication sho 57-182583 communique

Patent documentation 7: US Pat the 4th, 538, No. 537 communiques

Patent documentation 8: US Pat the 3rd, 455, No. 263 communiques

Patent documentation 9: US Pat the 4th, 363, No. 630 communiques

Patent documentation 10: japanese kokai publication sho 61-105292 communique

Patent documentation 11: japanese kokai publication hei 7-81550 communique

Patent documentation 12: japanese kokai publication hei 7-156791 communique

Summary of the invention

Invent problem to be solved

The present invention proposes in order to solve the problem that exists in the above-mentioned prior art; Its purpose is to provide a kind of current for the central tunnel portion of the stern that effectively utilizes twin shaft stern catamaran oceangoing ship, especially improves the twin shaft stern catamaran oceangoing ship of propulsion coefficient through the tunnel portion between improvement stern shape and the stern fin.

Solve the means of problem

The twin shaft stern catamaran oceangoing ship that the 1st aspect of the present invention is put down in writing is to have in the twin shaft stern catamaran oceangoing ship of two screw propellers, it is characterized in that, comprising: drive two said screw propellers and advance the propulsion unit of said twin shaft stern catamaran oceangoing ship; With two stern fins on the hull that is arranged on said twin shaft stern catamaran oceangoing ship, the set positions at the center of the axle drive shaft of two said screw propellers is that the center shaft of relative two said stern fins squints respectively.

According to above-mentioned formation; Owing to have the center shaft generation out-of-position screw propeller of the relative stern fin in center of axle drive shaft; Therefore in twin shaft stern catamaran oceangoing ship, can utilize the current of the stern fin direction opposite rear, thereby can increase the wake gain with hand of rotation screw propeller.

At this; " twin shaft stern catamaran oceangoing ship " be meant that two are parallel to each other about having not in the elongated bottom hull (main body) of underwater and water direct contact; On the quarter middle body has tunnel (tunnel) portion; And about be respectively equipped with at least one propulsion unit on the center shaft of each main body, be provided with the boats and ships of two above propulsion units altogether.Through being designed to twin shaft stern catamaran oceangoing ship, can design the stern fin that is provided with in order to ensure the stability of hull littler, and can increase loading space.

" screw propeller (propeller) " is meant the device that the output of propulsion units such as driving engine or motor is converted into the propulsive force of boats and ships, for example can adopt possess a plurality of blades (fin) of being used to obtain propulsive force, support blade and transmit the device that constitutes from the propeller hub (leaf hub (hub)) of the output of axle and other parts.As long as possess rotational force when using, can bear the rigidity of fluid resistance etc. and the fastness to water that can adapt to environment under water all the time, then can adopt any one materials such as metal, pottery, resin as the unit that is used to advance.

" propulsion unit " is meant the unit that drives screw propeller and advance boats and ships, can comprise the sustainer, main engine that drives the common screw propeller (screw) that is used for general boats and ships, counter rotating propeller, nozzle propeller etc. or by motor-driven electric pod propulsion propelling unit, mechanical activator pod propulsion propelling units such as (Z actuators) etc.

" stern fin (skeg) " vertically extends " fin " columnar structure thing from boat bottom.Even be not called as the stern fin, be positioned at screw propeller the place ahead substantially, and the shipform of the coursekeeping when being used for seeking boats and ships equally and advancing or the category that also belongs to the present invention's alleged " stern fin " is set.

" center shaft of stern fin " is meant and runs through stern fin in-to-in axle; For example in these boats and ships; Near the position center of gravity in the cross section that will be referred to as the part of stern fin with planar interception and obtain perpendicular to the working direction of boats and ships, the line that is formed by connecting till boats and ships the place ahead to the rear.

Usually; Adopt rotating shaft and the center shaft form consistent with each other of stern fin of the screw propeller of propulsion unit, " set positions is squinted for relative center shaft respectively " of the present invention is meant that the shaft center for the propulsion coefficient screw propeller that improves boats and ships is set to depart from the center shaft of stern fin.

" stern fin laterally " is meant the inboard or outside of a pair of stern fin.

The 2nd aspect of the present invention is characterized in that, in the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 1st, being put down in writing, according to the hand of rotation separately of two said screw propellers, changes said out-of-position direction separately.

At this, " according to hand of rotation, changing said out-of-position direction separately " is meant; For example with when when stern-side is observed; If screw propeller is rotated in a clockwise direction, then the stern fin squints to the right relatively, if screw propeller rotates along anticlockwise direction; The relative stern fin state of grade that squints left then, change out-of-position left and right directions.For example, in twin shaft stern catamaran oceangoing ship, when stern-side is observed; Under many circumstances, through the upwelling from the tunnel-like hull bottom recess of central authorities, the stern fin in the left side produces the anti-clockwise current; Stern fin on the right side produces clockwise current, and at this moment, " according to hand of rotation; change said out-of-position direction separately " is meant left screw and towards the right side right side screw propeller moved towards left avertence.The purpose of doing like this is that the spontaneous current at stern fin rear are collided the rotation of screw propeller the other way around with it relatively, thereby increase the suffered adverse current of screw propeller as much as possible.According to boats and ships, there is the identical or opposite situation of hand of rotation of two screw propellers, all can embodiment of the present invention for these boats and ships.

According to above-mentioned formation, set offset direction owing to be adapted to the hand of rotation of screw propeller, therefore can increase the vector summation of screw propeller as much as possible in the suffered adverse current of its plane of revolution.

The 3rd aspect of the present invention; It is characterized in that; In the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 1st or the 2nd, being put down in writing, confirm said out-of-position amplitude around the roughly maximum point of the on-cycle of a circle according to the annulus of drawing along 70～80% radiuses that distribute with the wake in the screw propeller face.

According to above-mentioned formation; Derivation is adapted to the offset amplitude of the best of shape and state of the quarter of a ship of these boats and ships; The adverse current of farthest utilizing the conduct circulation at the stern fin rear that screw propeller catches to be estimated, thus can obtain increasing the stern shape of wake gain.

At this, " in the screw propeller face wake distribute " is meant the velocity distribution of the current of the inflow screw propeller face that the hull shape by quarter of a ship of following propulsion of ship, etcetera, structure portion etc. cause.

" along the annulus of drawing with 70～80% radiuses around the roughly maximum point of the on-cycle of a circle " is meant the point that can define through following method: for example in the circumference of drawing with 70～80% radiuses of said screw propeller; On said circumference, the flow vector VT that flows into screw propeller is carried out integration, this is obtained maxim as the function of the rotating shaft coordinate of screw propeller.

Circulation is such conception of species; It not only comprises said circulation on the fluid mechanics (loop curve in flow carries out full Zhou Jifen to the product of the vector of the tangential direction of each point and line segment and the value obtained); But also comprise a generalized concept, this generalized concept (back will be expressed as " being equivalent to the on-cycle value ") comprise use along the flow vector cyclicity of the circumference of screw propeller rotation the value obtained.

At this; For short-cut calculation, on the circumference that 70～80% radiuses that distribute with wake are drawn, carry out integration, but in order to obtain the best rotating shaft coordinate of screw propeller more accurately; Also can be in whole middle computation cycles of screw propeller face, and the propulsive force of additional screw propeller face is obtained maxim.

The 4th aspect of the present invention; It is characterized in that; In the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 1st or the 2nd, being put down in writing; The hand of rotation of the said screw propeller that twin shaft is driven is set at: when said stern-side was observed said twinscrewvessel tail binary boats and ships, the said screw propeller that is positioned at the left side was rotated in a clockwise direction, and the said screw propeller that is positioned at the right side rotates along anticlockwise direction.

In view of the above; The current that will produce symmetrically at the stern fin of twin shaft stern catamaran oceangoing ship act on screw propeller effectively; Not only increase the wake gain thus, and avoided acting on hull, therefore help the steady steaming of boats and ships because of rotating the out-of-balance force that causes in the same direction.

At this, " twin shaft drive said screw propeller " be not meant two screw propellers be set in a rotating shaft, and be meant that two screw propellers are respectively by the form of different axle drive shaft rotations.

The 5th aspect of the present invention is characterized in that, in the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 1st or the 2nd, being put down in writing, reverses the rear portion of two said stern fins along the direction opposite with the hand of rotation of two said screw propellers.

At this; " reverse on the contrary " and for example be meant under the state that screw propeller is rotated in a clockwise direction when the boats and ships rear is observed with hand of rotation; The stern fin is out of shape towards anticlockwise direction; Promptly when twin shaft stern catamaran oceangoing ship advances, when being observed from the boats and ships rear, the current that form along stern fin surface are left-hand revolution.In view of the above, relative screw propeller becomes opposite mobile of hand of rotation rotary current and acts on.

Distortion comprises all forms of change, change stern fin-shaped shape.That is to say; The shape of reversing as the court of this stern fin direction opposite with the hand of rotation of screw propeller; Can take slowly crooked shape from the place ahead of stern fin; Also can take near stern fin rear sharply crooked shape, when can also take to bring into play the original function of stern fin, under the situation that less increases friction drag, produce the shape that flows that the propulsion coefficient actv. of screw propeller is become rotary current.As the formation method, can adopt same material to form with hull bottom, also can be used as and independently part detachable ground setting of hull bottom, so that can change the stern fin.For material, as long as can realize stably continuing to produce the purpose of rotary current, then no matter metal, plastics, pottery etc. all can.

According to above-mentioned formation, reverse through giving the setting of stern fin, make flow vector act on screw propeller more effectively, thus can be with the adverse current maximization of colliding with screw propeller.

The 6th aspect of the present invention is characterized in that, in the described twin shaft stern catamaran oceangoing ship, said propulsion unit is two pod propulsion propelling units aspect the of the present invention the 1st.

At this; " pod propulsion propelling unit " is meant in the hollow container of spindle-type motor is set; Propelling unit through the electric power rotating screw or mechanical type Z actuator etc. are the propulsion units that can freely set the position relation of stern fin and propulsion unit to a certain extent.

According to above-mentioned formation, compare with the method that the axle drive shaft of screw propeller is set in the stern fin, can set the offset amplitude of the center shaft of relative stern fin with cooresponding degree of freedom.

The 7th aspect of the present invention is characterized in that, in the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 6th, being put down in writing, has the connecting portion transversely that said pod propulsion propelling unit is connected to said stern fin.

Constitute according to this, be arranged on the stern fin transversely, therefore, can connecting portion be configured littler with vertical bonded assembly contrast owing to connect the angle of rake connecting portion of pod propulsion.

The 8th aspect of the present invention is characterized in that, in the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 6th or the 7th, being put down in writing, said pod propulsion propelling unit is a driven type.

Through adopting the pod propulsion propelling unit of driven type, for example, can dwindle the mechanism that is used for rotating screw with the contrast that adopts mechanical type Z actuator, therefore can reduce to be used for the pod propulsion propelling unit is connected to the connecting portion of stern fin.

The 9th aspect of the present invention; It is characterized in that; In the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 1st or the 2nd, being put down in writing; Said propulsion unit is for driving the sustainer, main engine (main frame pass) of two said screw propellers, and said stern fin is at the protrusion that transversely has the axle drive shaft of accommodating said screw propeller of stern fin.

At this, " sustainer, main engine (main frame pass) " is meant the devices such as driving engine that can produce mechanical energy continuously.For example, if adopt the formation that will drive two screw propellers respectively with different sustainer, main engines, the sustainer, main engine quantity that twin shaft stern catamaran oceangoing ship then of the present invention is had is two.But it may not be essential possessing two sustainer, main engines, also can adopt the formation of utilizing a sustainer, main engine to drive two screw propellers.

According to above-mentioned formation, said stern fin is at the protrusion that transversely has the axle drive shaft of accommodating screw propeller of stern fin, need not to be provided for especially to accommodate the structure of the axle drive shaft of screw propeller thus, and can dwindle protrusion.

The 10th aspect of the present invention is characterized in that, has two stern fins on the quarter and is driven in the twin shaft stern catamaran oceangoing ship of two screw propellers by twin shaft, comprising: the boundary 1ayer sucking hole that is arranged on formed tunnel portion between two said stern fins; From said boundary 1ayer sucking hole water is attracted the attraction unit of coming in; With the discharge orifice of discharging the water that attracts to come in through said attraction unit.

" boundary 1ayer " is meant the slack-off zone of the speed that influences that receives when boats and ships advance with the hull bottom friction.That is, in the little fluid of viscosity such as water, be suitable for substantially, be present near the velocity gradient of body surface zone big, that can't ignore viscosity and be called boundary 1ayer though ignore the perfect fluid theory of viscosity.

" boundary 1ayer sucking hole " also comprises the formation of the water and the water beyond the boundary 1ayer of suction side interlayer so long as the water of suction side interlayer gets final product.And the water that the boundary 1ayer sucking hole is preferably boundary 1ayer all sucks, but also only in the water of suction side interlayer near the water the king-sized hull bottom outside face of drag effects of twin shaft stern catamaran oceangoing ship.

The 11st aspect of the present invention is characterized in that, in the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 10th, being put down in writing, said boundary 1ayer sucking hole is arranged near the inlet portion of said tunnel portion.

At this, " inlet portion of tunnel portion " is meant the face of bow-side one end of the hull bottom in the face of the tunnel portion that formation is become with two stern fin-shapeds by hull bottom.

The 12nd aspect of the present invention is characterized in that, in the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 1st or the 2nd, being put down in writing, the width dimensions of said boundary 1ayer sucking hole is set at the width dimensions that is substantially equal to said tunnel portion.

At this, " width dimensions " of tunnel portion is meant the beam direction size of formed tunnel portion between two stern fins that are arranged on stern.

The 13rd aspect of the present invention is characterized in that, in the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 10th or the 11st, being put down in writing, the angle of the formed leaning angle of the relative horizontal direction of outside face of said tunnel portion is more than 15 degree.

The 14th aspect of the present invention; It is characterized in that; In the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 10th or the 11st, being put down in writing; Said discharge orifice is set to two at least, comes said twin shaft stern catamaran oceangoing ship is handled from the amount of the said water of these two said discharge orifices discharges through change.

The 15th aspect of the present invention; It is characterized in that; In the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 14th, being put down in writing; From said boundary 1ayer sucking hole to the path of said discharge orifice, being provided with two said attraction unit, change from two said discharge orifice drain water amounts through controlling these two said attraction unit.

The 16th aspect of the present invention; It is characterized in that; In the twin shaft stern catamaran oceangoing ship of aspect the of the present invention the 14th, being put down in writing; From said boundary 1ayer sucking hole to the path of said discharge orifice, being provided with the movable part that is used to change the current that form through said attraction unit,, change from two said discharge orifice drain water amounts through controlling this movable part.

At this, the movable parts of current " change " is meant that for example being arranged on being used in the path changes from the foliated lamellar movable part of the ratio of two discharge orifice drain water amounts, controls from the valve of two discharge orifice drain water amounts etc. respectively, has and utilize the means that attract beyond the unit to change the possessive construction of the movable part of current substantially.

Beneficial effect

According to the present invention; Through adopting twin shaft stern catamaran oceangoing ship; The stern fin that is provided with for the stability of hull can adopt small-sized stern fin, and the stern fin is as the obstacle in screw propeller the place ahead and the harmful effect that wake is produced diminishes thus, and through skew is set; Relative screw propeller can be increased in the flow vector composition of useful effect on the propulsion coefficient at stern fin rear, thus provide improve propulsion coefficient aspect energy-conservation, consider better boats and ships.

Promptly; Set the formation of its position if adopt the center shaft of the relative stern fin of centre of gration that makes screw propeller to squint respectively; Then can increase the vector summation of screw propeller in the suffered adverse current of its plane of revolution; Can the upwelling that be formed on tunnel portion effectively be utilized as the adverse current of screw propeller, therefore can improve the propulsion coefficient of twin shaft stern catamaran oceangoing ship.

And, set offset direction through the hand of rotation that is adapted to screw propeller, can the vector summation maximization of screw propeller in the suffered adverse current of its plane of revolution can be realized farthest improving propulsion coefficient in view of the above.

And, be adapted to the shape of boats and ships quarter of a ship and the optimized migration amplitude of state through deriving based on the circulation of flowing, can utilize the adverse current at the stern fin rear that screw propeller catches to come positively to improve propulsion coefficient.

And; If the screw propeller that adopts the hand of rotation of the screw propeller that will be driven by twin shaft to be set on the left of when said stern-side is observed twin shaft stern catamaran oceangoing ship, being positioned at is rotated in a clockwise direction; Be positioned at the formation of the screw propeller on right side along the anticlockwise direction rotation; Then can the upwelling that be formed at tunnel portion be effectively utilized the adverse current into screw propeller, therefore can improve the propulsion coefficient of twin shaft stern catamaran oceangoing ship.

And through reversing the rear portion of stern fin, screw propeller effect and the rightabout current of hand of rotation can increase the adverse current of colliding with screw propeller relatively, can realize the maximization of propulsion coefficient.

And; Through adopting the pod propulsion propelling unit; Can cancel the structure or the etcetera that are used to drive screw propeller in screw propeller the place ahead; So can further reduce of the harmful effect of the object of the obstacle that constitutes screw propeller the place ahead to the wake generation, and can set offset amplitude with cooresponding degree of freedom, therefore can screw propeller be set in best position aspect the raising propulsion coefficient.

And, be arranged on the stern fin transversely owing to connect the angle of rake connecting portion of pod propulsion, compare during with vertical the connection, can dwindle connecting portion.So, through constituting small-sized connecting portion, the friction drag that causes by connecting portion in the time of can reducing the propelling of twin shaft stern catamaran oceangoing ship, and can connecting portion be provided with low cost.

And, through adopting the pod propulsion propelling unit of driven type, can further dwindle connecting portion, the friction drag that causes by connecting portion in the time of therefore can further reducing the propelling of twin shaft stern catamaran oceangoing ship.

And, through in being arranged at the protrusion transversely of stern fin, accommodating axle drive shaft, can be at position configuration screw propeller from the axle drive shaft of stern fin towards lateral excursion.Therefore, can also dwindle protrusion, the friction drag that is caused by the structure of accommodating axle drive shaft in the time of can reducing the propelling of twin shaft stern catamaran oceangoing ship can provide twin shaft stern catamaran oceangoing ship with low cost.

And,, can suppress the outside face separated boundary layer of portion from the tunnel through water by the boundary 1ayer sucking hole suction side interlayer that is arranged on tunnel portion.In view of the above, can suppress because of separation of boundary layer forms and common current in the opposite direction, can suppress resistance increases.Thereby, can improve the propulsion quality of twin shaft stern catamaran oceangoing ship.

And, if adopt the boundary 1ayer sucking hole is arranged near the formation the inlet portion of tunnel portion, then take place easily in the separate areas of boundary 1ayer at degree of dip steep variation because of hull bottom, can be in the front in this zone (in front) the suction side interlayer.Thereby the outside face that can suppress boundary 1ayer portion from the tunnel effectively separates.

And, if with the width dimensions of boundary 1ayer sucking hole be set at the width dimensions of tunnel portion about equally, then can be along whole tunnel portion's suction side interlayer, the outside face that therefore can suppress boundary 1ayer portion from the tunnel effectively separates.

And if adopt the formation of angle more than 15 degree of the formed leaning angle of the relative horizontal direction of outside face of tunnel portion, then prior art moves on to stern-side with the inclination starting point of hull bottom relatively.In view of the above, can increase the carrying capacity of twin shaft stern catamaran oceangoing ship, improve its transport efficiency.

And, possess two discharge orifices if adopt, and change formation from discharge orifice drain water amount, for example need not to operate pod propulsion propelling unit or steering unit, can handle twin shaft stern catamaran oceangoing ship.

And, attract the unit to change through controlling two from two discharge orifice drain water amounts, the intake quantity that can combine thus to change the boundary 1ayer sucking hole improves the manoeuvre of ship effect.

And, change from two discharge orifice drain water amounts through the control movable part, for example under the situation that only possesses an attraction unit, also can handle twin shaft stern catamaran oceangoing ship thus.

Description of drawings

Fig. 1 is an External view of observing the related twin shaft stern catamaran oceangoing ship of embodiment of the present invention 1 from oblique rear;

Fig. 2 is the concept map that employed stern fin and the angle of rake position of pod propulsion relation in the boats and ships of Fig. 1 are shown;

Fig. 3 be model utility the mode chart of mobility status around the stern of existing single hull (single shaft ship, single-blade ship) is shown;

Fig. 4 is the mode chart that the mobility status around the stern fin of the related twin shaft stern catamaran oceangoing ship of embodiment of the present invention 1 is shown;

Fig. 5 is the mode chart that the summary situation of observing the related twin shaft stern catamaran oceangoing ship of embodiment of the present invention 2 from the rear is shown;

Fig. 6 is along near the section drawing the stern of the twin shaft stern catamaran oceangoing ship of C1-C2 line cut-away view 5;

Fig. 7 is the mode chart that the summary situation of observing the related twin shaft stern catamaran oceangoing ship of embodiment of the present invention 3 from the rear is shown;

Fig. 8 is the stern fin in-to-in mode chart of the twin shaft stern catamaran oceangoing ship of instruction diagram 7;

Fig. 9 is the mode chart that the propulsive force distribution of general screw propeller is shown;

Figure 10 is related screw propeller fwd flow vector and a wake distribution graph of embodiment of the present invention 4;

Figure 11 is the on-cycle contour map that the optimal location of the related propeller drive shaft of embodiment of the present invention 4 is shown;

Figure 12 is the related three-dimensional aerial view of on-cycle of embodiment of the present invention 4;

Figure 13 be model utility illustrate near the stern of the twin shaft stern catamaran oceangoing ship of embodiment 5 of the present invention therein near the heart along the section drawing of the state of fore-and-aft direction intercepting;

Figure 14 is the mode chart that the summary when the twin shaft stern catamaran oceangoing ship of observing embodiment 5 of the present invention from the rear is shown constitutes;

Figure 15 is the mode chart that the summary situation when the hull bottom side is observed the tunnel-like recess of twin shaft stern catamaran oceangoing ship of embodiment 5 of the present invention is shown;

Figure 16 is the mode chart that the summary situation when the hull bottom side is observed the tunnel-like recess of twin shaft stern catamaran oceangoing ship of embodiment 6 of the present invention is shown;

Figure 17 is the mode chart that the summary situation when the hull bottom side is observed the tunnel-like recess of twin shaft stern catamaran oceangoing ship of another program of embodiment 6 of the present invention is shown;

Figure 18 is the mode chart that the summary when the twin shaft stern catamaran oceangoing ship of observing embodiment 7 of the present invention from the rear is shown constitutes;

Figure 19 is the mode chart that the summary when the twin shaft stern catamaran oceangoing ship of observing embodiment 8 of the present invention from the rear is shown constitutes;

Figure 20 be model utility illustrate near the stern of existing twin shaft stern catamaran oceangoing ship therein near the heart along the section drawing of the state of fore-and-aft direction intercepting.

Nomenclature:

1: hull

2A, 2B, 3A, 3B: skew (offset)

11,12,51,52: the stern fin

11A, 12A, 51A, 52A: center shaft

21,22,23,24: gondola pillar (connecting portion)

210,220,230,240: the pod propulsion propelling unit

2101,2201,3101,3201: screw propeller

2101A, 2201A, 3101A, 3201A: screw propeller axle center

310,320: sustainer, main engine direct-connection type propelling unit

3202: axle drive shaft

3203: sustainer, main engine

61,62: protrusion

70: the boundary 1ayer sucking hole

71,71A, 71B: discharge orifice

72,72A, 72B: path

73,73A, 73B: impeller (attraction unit)

74,74A, 74B: motor (attraction unit)

75: movable part

The specific embodiment

With reference to the accompanying drawings the mode that is used for embodiment of the present invention is described.Need to prove, below with model utility the needed scope of explanation that is used to reach the object of the invention is shown, with the needed scope of the explanation that relevant portion of the present invention mainly is described, can be for the part of omitting explanation with reference to known technology.

Embodiment 1

Fig. 1 is an External view of observing the related twin shaft stern catamaran oceangoing ship of embodiment of the present invention 1 from oblique rear.As shown in Figure 1, hull 1 and stern fin 11, stern fin 12 and and then stern fin 11, stern fin 12 be arranged on its rear pod propulsion propelling unit 210 and pod propulsion propelling unit 220 in couples, be arranged as two groups on the quarter.When existing at interval between the axial line of the screw propeller 210 that dots respectively and the axial line of stern fin 11, it is labeled as skew 2A, when existing at interval between the axial line of the axial line of screw propeller 220 and stern fin 12, it is labeled as skew 2B.At this, having the angle of rake twin shaft stern of pod propulsion catamaran oceangoing ship is an example, also fully can embodiment of the present invention in the twin shaft stern catamaran oceangoing ship that is through with common axle.

Fig. 2 is the position relation about stern fin 11 and pod propulsion propelling unit 210, illustrates from the pie graph of the viewed situation in rear of hull 1.Among Fig. 2, (, being called volute type (cochlear) ship type) stern shape that reverses the stern fin of enumerating in this embodiment to be adopted at this.The screw propeller 2101 of pod propulsion propelling unit 210 is when advancing, and right-hand revolution produces propulsive force.In the stern fin 11 in left side, transversely being applied on cross section as shown in the figure reversed.Towards the left side, center shaft 11A bottom part twists respectively towards the right side with the center shaft 11A top part of stern fin.In view of the above; Flowing from right to left when the top part of the center shaft 11A of stern fin can add the rear from hull 1 that uprush causes and observes; Therefore flowing from left to right when the bottom part of the center shaft 11A of stern fin can add the rear from hull 1 that uprush causes and observes can increase the adverse current (counter flow) of relative screw propeller 2101.

The center shaft 11A of stern fin is meant and runs through stern fin in-to-in axle; For example in these boats and ships; Near the position center of gravity of the section drawing that will be referred to as the part of stern fin with planar interception and obtain perpendicular to the working direction of boats and ships, the line that couples together till boats and ships the place ahead to the rear.

As shown in Figure 2, the screw propeller axle center 2101A of pod propulsion propelling unit 210 takes place to squint and be provided with from the axle center 11A that is applied in the stern fin 11 that reverses.Skew is meant the deviation distance that is provided with intentionally in order to obtain the fluid mechanics effect.

Fig. 3 be model utility the mode chart of mobility status around the stern of existing single hull is shown, Fig. 4 is the mode chart that the mobility status around the related stern fin of embodiment of the present invention 1 is shown.

As shown in Figure 3, at the quarter of a ship 31 of general single hull (single shaft ship, single-blade ship), when propulsion of ship, left side on the quarter produces clockwise mobile 35A, and right side on the quarter produces the mobile 35B of anti-clockwise.

Generally speaking; The axle drive shaft 311A of screw propeller is set on the longitudinal centerline 311 of this quarter of a ship 31; And when the screw propeller (not shown) of clickwise is set; (observing from the stern rear) axle drive shaft left side produces the mobile 35A identical with the hand of rotation of screw propeller, and (observing from the stern rear) axle drive shaft right side produces the opposite mobile 35B of hand of rotation with screw propeller.The propulsive force that is produced by screw propeller is maximum when the direction opposite with the hand of rotation of screw propeller mobile tangent, so from about the screw propeller, the propulsive force that offers boats and ships is bigger on the face on screw propeller right side.

For the stern fin, to compare with the quarter of a ship of this general single hull, shape is less, and also narrower from its width of size, so flow stable because of eddy current can't form of the wake flow of stern fin.

With regard to common twin shaft stern catamaran oceangoing ship; Because of possessing the phenomenon that stern shape characteristic that the stern fin produces can cause the quarter of a ship that is different from general single hull as follows: produce anti-clockwises near the stern fin 11 in tunnel-like hull recess (being called " tunnel the portion ") left side of central authorities and flow, and produce clockwise flowing near the stern fin 12 on tunnel portion right side.When observing, we can say opposite the flowing of quarter of a ship that produces respectively with above-mentioned general single hull from hull stern rear.

Be positioned at the shape of the stern fin 11 in left side when observing from the rear in two stern fins of twin shaft stern catamaran oceangoing ship involved in the present invention shown in Fig. 4.

The stern fin 11 in left side twists from hull the place ahead lentamente.When propulsion of ship; Follow upwelling; About the stern fin, produce the mobile 15A of nature, 15B,, combine with the stern shape of twin shaft stern catamaran oceangoing ship according to the shape that twists of stern fin 11; 11B strengthens the mobile 15B of anti-clockwise on the right side of stern fin 11, produces the zone that becomes rotary current.Through making screw propeller face this zone, screw propeller becomes stronger in the adverse current of the suffered upwelling F (referring to Fig. 5) of the right half part R1 of its plane of revolution, can increase the wake gain.

Embodiment 2

When the marine propulsion system in the future of considering not rely on fossil fuel, in existing propelling unit, the highest as angle of rake effect of the pod propulsion of prerequisite and reliability with electric propulsion.On the other hand, the disadvantage of electric propulsion is its energy conversion efficiency, thinks that at present there is about 12～13% loss in it.Therefore, advance with the diesel oil of the existing sustainer, main engine direct connection that 1～2% transmission loss only takes place and to compare, can't lose with avoiding and exceed 10～11 percentage points.In order to eliminate this problem, need maximally utilise the ship type design of the angle of rake characteristic of pod propulsion.

The twin shaft stern catamaran oceangoing ship of this embodiment is realized the significantly reduction of the friction drag of gondola pillar thus through the angle of rake gondola pillar of the pod propulsion that side-play amount is set (connecting portion) being installed along laterally being provided with of stern fin.Therefore, through reducing the friction drag of gondola pillar, can improve the propulsion coefficient of twin shaft stern catamaran oceangoing ship.

Fig. 5 illustrates the mode chart that the summary of observing the related twin shaft stern catamaran oceangoing ship of embodiment of the present invention 2 from the rear constitutes.As shown in Figure 5, the quarter of a ship 13 of hull 1 has a pair of

stern fin

11,12 and is separately positioned on a pair of pod propulsion propelling unit 210,220 at the tight rear of a pair of

stern fin

11,12.

Using the interval marking between the center shaft 11A of axial line 2101A and stern fin 11 of the screw propeller 2101 that x representes respectively is skew 2A, and the interval marking between the axial line 2201A of screw propeller 2201 and the center shaft 12A of stern fin 12 is skew 2B.At this; Boats and ships (twin shaft stern catamaran oceangoing ship) with the angle of rake twin shaft double body type of pod propulsion stern shape are an example; As after described in the embodiment 3 stated, also fully can embodiment of the present invention in the boats and ships with the twin shaft double body type stern shape that runs through axle drive shaft (twin shaft stern catamaran oceangoing ship).

When embodiment 2 related twin shaft stern catamaran oceangoing ships advance; In near the quarter of a ship that the hull bottom 20 of stern fin 11, stern fin 12 and hull 1 is surrounded 13 the tunnel-like recess 14, produce that the with dashed lines hollow arrow is represented among Fig. 5 towards quarter of a ship 13 directions (the front direction when seeing Fig. 5) than uprush F.Its reason is, as along shown in the section drawing of the Fig. 6 the quarter of a ship 13 of C1-C2 line intercepting twin shaft stern catamaran oceangoing ship near, surrounds hull bottom 20 run-off the straight sharp of the hull 1 of tunnel-like recess 14, and uprises gradually towards quarter of a ship 13.Therefore, the floating line L that dots in the drawings below along with the propelling of hull 1, produces the upwelling F towards oblique upper along the inclination of hull bottom 20.And, be positioned at the center shaft generation out-of-position desired location of relative stern fin 12 for making pod propulsion propelling unit 220, the vertical bonded assembly connecting portion 24 to use dashdotted imaginary line to represent among Fig. 6 need be set.That is to say, need its longitudinal size bigger, and in order to ensure moment strength, sectional area also must become greatly as connecting portion 24, thus its as a result the face area of connecting portion 24 can become very big.This connecting portion 24 so become the reason that produces big friction drag, causes propulsion coefficient to reduce because of rubbing with upwelling F.This point also is the same to another pod propulsion propelling unit 210.

Therefore; As shown in Figure 5; The twin shaft stern catamaran oceangoing ship of this embodiment 2 is through being connected to stern fin 11 and stern fin 12 transversely with pod propulsion propelling unit 210 and pod propulsion propelling unit 220; Thereby the connecting portion face area is diminished, realized reducing taking place the purpose of the friction drag that friction causes because of upwelling F and connecting portion.

That is to say; Pod propulsion propelling unit 210 is connected in stern fin 11 through the gondola pillar (connecting portion) 21 that is arranged on stern fin 11 inboards (being positioned at a side on stern fin 11 right sides when observing from the rear), and pod propulsion propelling unit 220 is connected in stern fin 12 through the gondola pillar (connecting portion) 22 that is arranged on stern fin 12 inboards (being positioned at a side in stern fin 12 left sides when observing from the rear).The position that makes pod propulsion propelling unit 210,220 that skew take place and be provided with usually than hull bottom 20 more near stern fin 11,12.Therefore, through pod propulsion propelling unit 210,220 being connected in the inboard of

stern fin

11,12, and compare,

gondola pillar

21,22 is diminished along the situation that vertically is connected in hull bottom 20 (referring to Fig. 6).That is, through

gondola pillar

21,22 is connected

stern fin

11,12 transversely, its result can set the face area of

gondola pillar

21,22 very little.And upwelling F is at pod propulsion propelling unit 210,220 and stern fin 11, between 12, than between pod propulsion propelling unit 210,220 and hull bottom 20, flowing slowlyer.

Therefore; Through gondola pillar 21 and gondola pillar 22 being arranged on stern fin 11 and stern fin 12 transversely, can being provided with the face area of gondola pillar 21 and gondola pillar 22 very little and can gondola pillar 21 and gondola pillar 22 being configured in the slower part of flow velocity.In view of the above, can reduce because of the resistance that gondola pillar 21 that out-of-position pod propulsion propelling unit 210 and pod propulsion propelling unit 220 be connected to hull 1 and gondola pillar 22 and upwelling F friction cause will take place.And,, therefore can gondola pillar 21 and gondola pillar 22 be provided with low cost owing to can be provided with gondola pillar 21 and gondola pillar 22 less.

As representing with arrow among Fig. 5, the screw propeller 2101 of pod propulsion propelling unit 210 and the screw propeller 2201 of pod propulsion propelling unit 220 rotate along opposite sense.More specifically, when observing from the rear, pod propulsion propelling unit 2101 clickwises, screw propeller 2201 left-hand revolutions, thus constitute so-called interior rotation of rotating.Therefore, utilize the right half part region R 1 of the plane of revolution of the screw propeller of being represented by the formed circle of long and short dash line 2101 in the drawings, pod propulsion propelling unit 210 can be used upwelling F as adverse current.Likewise, utilize the left-half area L 2 of the plane of revolution of the screw propeller of being represented by the formed circle of long and short dash line 2201 in the drawings, pod propulsion propelling unit 220 can be used upwelling F as adverse current.At this, adverse current is meant the current of the direction opposite with the hand of rotation of screw propeller, through utilizing this adverse current, can reduce can improve its propulsive force because of screw propeller rotates the loss that water causes.

And left-half area L 1 major part of the plane of revolution of screw propeller 2101 is positioned at the slower zone of current at the rear of stern fin 11 and gondola pillar 21.And the major part of the right half part region R 2 of the plane of revolution of screw propeller 2201 is positioned at the slower zone of current too.Therefore, can't the zone of upwelling F as adverse current can received because of the influence that skew causes takes place hardly.Thereby the center shaft of the relative stern fin 11 of axial line 2101A through making screw propeller 2101 squints, and can receive the adverse effect that upwelling F causes hardly.This point also is like this for screw propeller 2201.

Therefore, squint, can upwelling F be used as adverse current, thereby significantly improve propulsive force through making screw propeller 2101 and screw propeller 2201.

Thus, the upwelling F that can near the inclination of the hull bottom 20 the quarter of a ship 13 be caused is used in and improves on the propulsive force, therefore can the degree of dip of hull bottom 20 is provided with bigger.Thereby the inclination starting point that can make near the hull bottom 20 the quarter of a ship 13 was than more being partial to the rear in the past, thereby can increase the carrying capacity of twin shaft stern catamaran oceangoing ship.

As stated, the twin shaft stern catamaran oceangoing ship of this embodiment 2 squints through making the screw propeller 2101 and the center shaft of screw propeller 2201 relative stern fins 11 and stern fin 12, has improved propulsion coefficient.And,, can gondola pillar 21 and the friction drag that gondola pillar 22 causes with upwelling F generation friction be minimized through gondola pillar 21 and gondola pillar 22 are arranged on stern fin 11 and stern fin 12 transversely.

At this; In this embodiment; Through screw propeller 2101 and the interior side direction of screw propeller 2201 towards stern fin 11 and stern fin 12 are squinted, utilize the upwelling F of tunnel-like recess 14 to improve propulsive force, and when screw propeller 2101 and screw propeller 2201 when the lateral direction generation of stern fin 11 and stern fin 12 is squinted; Though adverse current effect step-down can improve the line navigation performance of twin shaft stern catamaran oceangoing ship.

Embodiment 3

The twin shaft stern catamaran oceangoing ship of this embodiment 3 is with changing to common sustainer, main engine direct-connection type propelling unit as the employed PODDED PROPULSOR of propulsion unit in the embodiment 2.The optimal location of screw propeller is positioned at from the center shaft of stern fin out-of-position place significantly inwards; But in common stern fin-shaped shape; Want the angle of rake screw propeller of configuration sustainer, main engine direct-connection type, need be provided for accommodating the structure of the axle drive shaft of screw propeller especially in this place, thereby difficulty comparatively.Therefore; The purpose of the twin shaft stern catamaran oceangoing ship of this embodiment is: stern fin-shaped shape is designed to very asymmetric; And the protrusion that stretches out is set in the inboard; Accommodate the angle of rake cardan shaft of sustainer, main engine direct-connection type herein, thus when using sustainer, main engine direct-connection type propelling unit, obtain and same high propulsion coefficient when using the pod propulsion propelling unit.Specifically, owing to significantly squinted towards the hull center side from stern fin center in the center of screw propeller, therefore stern fin-shaped shape is designed to asymmetrical shape, and bigger protrusion is set in the inboard.

Fig. 7 is the mode chart that the summary situation of observing the related twin shaft stern catamaran oceangoing ship of embodiment of the present invention 3 from the rear is shown.As shown in Figure 7, the quarter of a ship 53 of the hull 50 of the twin shaft stern catamaran oceangoing ship of this embodiment has a pair of stern fin 51 and stern fin 52, and then stern fin 51 and stern fin 52 are arranged on a pair of sustainer, main engine direct-connection type propelling unit 310 and the sustainer, main engine direct-connection type propelling unit 320 at its rear respectively.Among Fig. 7, the interval marking of the axial line 3101A of screw propeller 3101 and the center shaft 51A of stern fin 51 is skew 3A, and the interval marking of the axial line 3201A of screw propeller 3201 and the center shaft 52A of stern fin 52 is skew 3B.

The twin shaft stern catamaran oceangoing ship propelling of this embodiment 3 and the twin shaft stern catamaran oceangoing ship of embodiment 2 are likewise; In near when advancing the quarter of a ship 53 that the hull bottom 60 of stern fin 51, stern fin 52 and hull 1 is surrounded the tunnel-like recess 54, generation towards quarter of a ship 53 directions (the front direction when seeing Fig. 7) than uprush F.For this upwelling F is used as adverse current, screw propeller 3101 and screw propeller 3201 are squinted towards the inboard of center shaft 51A and center shaft 52A.But,, screw propeller 3101 and screw propeller 3201 are squinted if stern fin 51, stern fin 52 are designed to general existing tail fin shape.Therefore, stern fin 51 and stern fin 52 within it side be provided with the protrusion 61 and protrusion 62 of the axle drive shaft that is used to accommodate screw propeller 3101 and screw propeller 3201.

So, through outstanding protrusion 61 and protrusion 62 towards the inboard (tunnel-like recess 54 sides) of stern fin 51 and stern fin 52 are set, can screw propeller 3101 and screw propeller 3201 be configured in optimal location, in order to improving propulsion coefficient with upwelling F.

Fig. 8 is the scheme drawing from the stern fin 52 of the twin shaft stern catamaran oceangoing ship of hull central side observation Fig. 7, is to be used to explain stern fin in-to-in mode chart.Stern fin 52 possesses side-prominent protrusion 62 in it.Therefore, as with dashed lines among Fig. 8 is represented, take place under the out-of-position state at screw propeller 3201, portion is provided for driving the axle drive shaft 3202 and the sustainer, main engine 3203 that is connected in screw propeller 3202 of screw propeller 3201 within it.This point also is the same for the screw propeller 3101 of opposite side.

As stated; The twin shaft stern catamaran oceangoing ship of this embodiment 3 is through improving the tail fin shape; Need not to be provided for especially to accommodate the structure of the axle drive shaft of screw propeller; Can be at the optimal location of considering from propulsion coefficient of original very difficulty, i.e. the angle of rake screw propeller of out-of-position position configuration sustainer, main engine direct-connection type significantly inwards.In the twin shaft stern catamaran oceangoing ship of this embodiment 3, through upwelling F is utilized as adverse current, can significantly improve propulsion coefficient, its effect is head and shoulders above because of increasing the increase of the friction drag that causes towards the face area of the protrusion 61,62 that crosses out.And, reversing volute type (cochlear) the ship type of stern fin through employing, when further increasing the adverse current effect, can reduce further to improve propulsion coefficient towards the face area of the protrusion 61,62 that crosses out.

Have like this embodiment 3 in the twin shaft stern catamaran oceangoing ship of sustainer, main engine; Through design tail fin shape and the protrusion of accommodating axle drive shaft; Has following advantage: the structure that need not to be provided for especially accommodating axle drive shaft; Be that available less protrusion constitutes desired structure with low cost, cost required in the time of can reducing podularization formula propelling unit simultaneously rises.

Embodiment 4

Next, the method for obtaining the optimization point of the rotating shaft that screw propeller is set through algorithm is described.This method also can be used in the twin shaft stern catamaran oceangoing ship of embodiment 1～3.

Fig. 9 is the mode chart that the propulsive force distribution of general screw propeller is shown.

The aerofoil area of screw propeller is big more, and the propulsive force that produces during rotation is also big more, but the resistance of himself suffered water also becomes greatly, and promptly there is the relation of this contradiction in the screw propeller aerofoil.The maximum point of the propulsive force thought that learnt by calculating and general is positioned at from the distance of rotating shaft 70～80% scope for this screw propeller radius of rotation.But; Shape according to screw propeller; Propulsive force largest peaks position may be different, but aim of the present invention is to make the rotary current that produces in the screw propeller front to contact with screw propeller as adverse current as much as possible, also fully can embodiment of the present invention for such screw propeller.

Figure 10 is the flow vector and the wake distribution graph of the water at related stern fin 11 rears (front of screw propeller 2101) of embodiment of the present invention 4.This flow vector for example both can be measured through physical method with Experimental Establishment etc.; Also can be as the result of model experiment, computer modeling etc. and obtain; Approximate form obtains this prerequisite of flow vector that this stern fin periphery is produced according to boats and ships real-world operation that this stern fin 11 is installed the time as long as satisfy, and does not then limit any means.

Shown in figure 10, be endowed on the stern fin that reverses and produce that the left and right sides is non-symmetrical flows, can know on the right side zone that produces the bigger mobile expansion of wider vector along the left-hand revolution direction.The flowing of these left-hand revolutions the to be known as adverse current of the propulsion coefficient of improving screw propeller, i.e. rotary current.Area for the screw propeller that increases clickwise as far as possible contacts with the rotary current of this left-hand revolution is provided with skew to the right in the rotating shaft of screw propeller.And the optimum position of screw propeller on this out-of-position basis to the right, also will further be set in than the horizon through stern fin axle center and lean on last position slightly.

Explanation is used for the related function block (not shown) of embodiment of the deviation post of optimization propeller drive shaft below.

This embodiment for example comprises and constitutes (not shown) like the lower part: the flow vector data input part is used for input and keeps through experiment or simulate the flow vector that (emulation) resulting stern fin rear is produced; The radius input part, the scope that screw propeller rotation is produced propulsive force in water is imported as the radius of screw propeller and is kept; Maximum propulsive force is justified drawing section, is drawn near the circular trace (maximum propulsive force circle R) of the maximum propulsive force of generation that is positioned at its about 70～80% radiuses by the radius of being imported; Maximum propulsive force is justified R centre coordinate control part, is used for changing continuously maximum propulsive force and justifies the centre coordinate value of R and pass to maximum propulsive force circle drawing section; Flow vector V _TLeading-out portion is derived the flow vector V on the maximum propulsive force circle R by coordinate on the maximum propulsive force circle R and rotary current vector data _TFlow vector V _TIntegration part is with this flow vector V _TJustify on the R along a week carrying out line integral in maximum propulsive force; The curve rendering section is by the centre coordinate of maximum propulsive force circle R and the figure of curve plotting as a result of line integral.

At this, this embodiment for example realizes as software, and concrete function of bearing for each function block and concrete contact each other can have various distortion.Get final product so long as obtain the algorithm of best coordinates position of the rotating shaft of screw propeller based on circulation.And, each inscape of above-mentioned software through realizing above-mentioned various functions machinery, device, parts or carry out on computers this function algorithm, the software that is used to carry out the program of this algorithm or comprise this program, carry medium, ROM (read-only memory (ROM)) or lift-launch or built-in these computing machine or its part realizes.And; Also can be used as the computer installation that carries these and (comprise Personal Computer (PC); Have input part (keyboard etc.) as the central processing unit (CPU) that carries out data handing or calculating, the quantitative data input subscribed, show the data imported or data processed result picture display part (telltale etc.), memory storage (memory device, hard disk drive etc.) that various data are preserved in storage, be used for carrying out the signal conditioning package of bonded assembly adaptor union (USB, RS232C etc.) etc. with predetermined external equipment) realize.

When obtaining the optimization point of the rotating shaft that is used to be provided with screw propeller, roughly can adopt following order (not shown).That is, at first obtain the flow vector data.Import the flow vector that takes place at stern fin rear that obtains through experiment or simulation through the flow vector data input part.Then, through the radius input part, the scope that screw propeller rotation is produced propulsive force in water is imported as the radius of screw propeller and is kept.Then, through maximum propulsive force circle drawing section, draw near the circular trace (maximum propulsive force circle R) of the maximum propulsive force of generation that is positioned at its about 70～80% radiuses by the radius of this input.Justify R centre coordinate control part through maximum propulsive force, change maximum propulsive force continuously and justify the centre coordinate value of R and pass to maximum propulsive force circle drawing section.Then, through flow vector V _TLeading-out portion is derived flow vector V by coordinate and rotary current vector data on the maximum propulsive force circle R _TAt this, flow vector V _TThe maximum propulsive force that is meant the rotary current vector in the coordinate on the maximum propulsive force circle R is justified the composition of the tangential direction of R.Then, through flow vector V _TIntegration part is with this flow vector V _TJustify on the R along a week carrying out line integral in maximum propulsive force.Then, through the curve rendering section, by the centre coordinate of maximum propulsive force circle R and the figure of curve plotting as a result (not shown) of line integral.So, curve plotting is obtained contour line.Should be decided to be the optimum position by isocontour maximum.

At this; Above-mentioned flow vector legend was as both being made by the result who measures through physical method with Experimental Establishment etc.; Also can be as the result of model experiment, computer modeling etc. and obtain; Approximate form obtains this prerequisite of flow vector that this stern fin periphery is produced according to boats and ships real-world operation that this stern fin 12 is installed the time as long as satisfy, and does not then limit any means.

As stated, flow vector V _TIntegration part is about point (x, the flow vector V that y) locates on the circumference of maximum propulsive force circle R _T, on circumference,, carry out integration around a circle, with thus obtained value as circulating (mutually on duty) Γ.At this; About being equivalent to the on-cycle value; Said circulation is meant that loop curve in flow carries out full Zhou Jifen to the product of the vector of the tangential direction of each point and line segment and the value obtained on the fluid mechanics; And in this embodiment circulation be meant comprise use along the flow vector cyclicity of the circumference of screw propeller rotation the generalized concept of the value obtained, so be expressed as " the on-cycle value circulates=be equivalent to " among the present invention.And, when deriving the roughly maximum point of circulation, can consider that cost and cooresponding with it effect come design means.

Further, according to the screw propeller shape, propulsive force largest peaks position can be different, and 70～80% the position that the circumference that therefore carries out integration departs from that wake distributes is also harmless, does not hinder to obtaining appropriate result to change.

In the superincumbent description; To using the vector in the screw propeller face (whole face); And the situation of screw propeller also being carried out two-dimensional process is described, but also can adopt three-dimensional method to obtain skew, and can adopt the three-dimensional skew and the mode of screw propeller position obtained.At this moment, in above-mentioned content, obtain centre coordinate through maximum propulsive force circle R (x, y) definite circulation Γ, and on the Z in xyz space axle, draw numerical value and get final product by the each point of curve rendering section on the Z axle.

At this moment; " on the Z in xyz space axle, draw numerical value " and be meant that (x, y) well-determined Γ value for example adopt a plurality of curves that are limited to the two dimension of using the xy plane as curve to the centre coordinate that is illustrated in maximum propulsive force circle R intuitively; In each curve with the height of its value of color showing; Perhaps illustrate etc., can adopt the whole bag of tricks, this is not limited with contour line.So long as can then have no restriction through the means of visual confirmation Γ value and height thereof.

Since then on the basis, when the peak value of Γ near initial point, occurring through observing, with this point (x, y) coordinate is as the center shaft of the rotating shaft of screw propeller.When not finding peak value; Do not exceed in the scope of the radius of rotation of screw propeller in the relative side-play amount of the center shaft of stern fin; (x y), is drawn as the Γ value of result of calculation separately by the curve rendering section to change the coordinate of the rotating shaft of screw propeller in regular turn by maximum propulsive force circle R centre coordinate control part.

With regard to the peak value of the Γ the initial point near, near the nature of the center shaft of stern fin can produce rotary current, and the far place of decentering axle just can not produce rotary current originally, changed the center of the rotating shaft of screw propeller there howsoever, and the Γ value can not change.Therefore, if the peak value of Γ exists, it can be from the center shaft of stern fin place so far away, even should depart from the center shaft from the stern fin farthest in the scope about the radius of screw propeller yet.

So, confirm the center shaft that the size to this stern fin-shaped shape and screw propeller is rotated the roughly maximum screw propeller of propulsion quality of these boats and ships.

Shape according to boats and ships; Even used the pod propulsion propelling; Also exist the influence receive factors such as physics restriction can't be in the possibility of the rotating shaft of optimal location setting screw propeller; This moment the rotating shaft of screw propeller is set in the best of obtaining through Theoretical Calculation the rotating shaft coordinate near, can say that just propulsion quality is roughly maximum above therefore.Aim of the present invention is that the position through tail fin shape and screw propeller concerns and improves propulsion quality; When embodiment of the present invention; Be not defined as and extremely strictly maximize propulsion quality,, just meet the application's aim as long as make propulsion quality obtain maximization in fact.

At this; Above-described only is for the optimum position of the rotating shaft of obtaining screw propeller and use an example of the method for software; Also can adopt the method for obtaining the rotating shaft of the maximum screw propeller of propulsive force according to the measured value that obtains through experiment, this experimental example is as for making current from the fixed stern fin-shaped of frontal crash shape, identical environment when producing with propulsion of ship; Make the work of pod propulsion propelling unit at its rear, measure experiments such as the resulting power of this pod propulsion propelling unit thus.

Figure 11 and 12 illustrates to be used to obtain by the on-cycle contour line that is depicted as curve of the centre of gration axial coordinate of the radius of the stern fin-shaped shape of these boats and ships and screw propeller, the well-determined screw propeller of shape and this isocontour three-dimensional display result's mode chart.Draw out the result of the approximate circulation Γ that will in above-mentioned series of steps, derive.Figure 11 is the figure that observes curve from Z-direction, and Figure 12 is the aerial view of this curve.

If the vector of the rotary current that produces at stern fin rear is defined within on the plane, where then can be arranged on and the size of the radius of rotation of screw propeller is obtained this approximate circulation according to the rotating shaft of screw propeller.(x is exactly the point that obtains maximum wake gain for screw propeller y), is to the size (radius of rotation) of this stern fin-shaped shape and the screw propeller screw propeller rotating shaft position of the best roughly to make the rotating shaft coordinate of the maximum screw propeller of this approximate circulation.

The propulsive force that obtains when next, advancing for effect, action and this boats and ships of the said embodiment that constitutes as stated increases effect and describes.

As shown in Figure 5, these boats and ships have two cover stern fin and the angle of rake combinations of pod propulsion.As shown in Figure 4, the stern fin is the shape that twists.With regard to the pod propulsion propelling unit, the left side pod propulsion propelling unit shown in Fig. 5 is rotated in a clockwise direction, and the right side gondola is that propelling unit rotates along anticlockwise direction, and is set to respectively to have the side-play amount of form shown in Figure 10 towards the center shaft side of hull separately.

When these boats and ships begin to advance, on the quarter and stern fin rear begin to produce current.Between the left and right sides stern fin of hull central authorities, produce current left and to the right respectively, as stated; Because the stern fin twists; Therefore produce rotary current about left side stern fin on its right side, produce rotary current in its left side about right side stern fin, and stronger than the current that are created in opposition side separately.That is to say, from the stronger rotary current of center shaft side generation of boats and ships.

For this rotary current is used as adverse current, the pod propulsion propelling unit is set, its central axis direction towards hull is squinted.In view of the above; Through skew is set; The rotary current that screw propeller can be produced the stern fin by twisted shapes more is used as adverse current; So with have extremely general stern fin-shaped shape and the angle of rake set positions of pod propulsion is compared for its axle center boats and ships consistent with the axle center of stern fin, increase propulsive force significantly.

Therefore; According to this embodiment 4; Can obtain combination to the distortion stern fin-shaped shape that amplifies rotary current and this tail fin shape and screw propeller and make the gain rotating shaft position of maximized screw propeller of wake; And can its best rotating shaft position setting comprise the pod propulsion propelling unit and the angle of rake screw propeller of sustainer, main engine direct-connection type of mechanical activator, so contributing aspect the fuel cost of the propulsion coefficient that improves various boats and ships, the various boats and ships of reduction.

And; Through adopting twin shaft stern catamaran oceangoing ship; The stern fin is set for the stability of hull can adopts small-sized stern fin, the stern fin is as the obstacle in screw propeller the place ahead and the harmful effect that wake is produced diminishes thus, and through the center shaft generation out-of-position screw propeller of the relative stern fin of shaft center is set; Can utilize the peculiar upwelling of twin shaft stern catamaran oceangoing ship to strengthen the rightabout current of hand of rotation with screw propeller at stern fin rear, can increase the wake gain.That is, through skew is set, relative screw propeller can be increased in the flow vector composition of useful effect on the propulsion coefficient at stern fin rear, thus provide improve propulsion coefficient aspect energy-conservation, consider better boats and ships.

And; Green phase makes the pod propulsion propelling unit of propulsion of ship skew take place and the stern fin of desired location to driving screw propeller; The structure that cardan shaft is passed through that does not exist single-shaft variant to advance the shipload biaxial type to advance ship etc. to be had in the front portion of screw propeller; Therefore can further reduce the harmful effect that the stern fin produces as the obstacle in screw propeller the place ahead and to wake; Elimination produces dysgenic current to the propulsion coefficient of screw propeller, and can the current that result from stern fin rear be acted on screw propeller best as adverse current, thereby can further improve propulsion coefficient.

Further; Can be on the basis of obtaining the flow vector data; With the input propeller radius with describe maximum propulsive force circle, continuously change the centre coordinate value of maximum propulsive force circle R and derive flow vector on the maximum propulsive force circle R, on maximum propulsive force circle to the flow vector value carry out full contour integration, through drawing the contour line that draws based on line integral result's curve, confirming this series of processes algorithmization of optimum position of isocontour maximum; Its result; Can realize making the computing of the optimum position that screw propeller is provided with to realize the method for designing of the stern shape of automation, the optimum position of this screw propeller setting makes the suffered adverse current of screw propeller become greatly in the combination of this tail fin shape and screw propeller.

For the angle of rake existing ship of pod propulsion that use comprises mechanical activator, only simply transform through making it that position generation out-of-position is set, just can improve propulsion coefficient, the effect of relative cost is high, and saves resource.

In addition; The factors such as variation of the drinking water of considering marine site that the salt concentrations such as pack ice zone of polar region are higher or also changing up and down or cause according to carrying capacity according to the viscosity of the different seawater of the navigation environments such as height of sea temperature; Can cause the size and the vector of wake to change; Make the deviation post of screw propeller can suitably change to the structure in best place through employing, should further improve propulsion coefficient, reduce fuel cost.

Embodiment 5

As implementing described in the mode 1～4; The present invention improves propulsive force through effectively utilizing the current that form in the tunnel-like recess (tunnel portion) between the stern fin, and the purpose of the twin shaft stern catamaran oceangoing ship of this embodiment 5 is particularly in obtaining maximum delivery power through the boundary 1ayer suction apparatus that is arranged on the tunnel portion between the stern fin.

The space that the stern fin and the hull bottom of twin shaft stern catamaran oceangoing ship are limited is known as tunnel portion, and the leaning angle of the relative horizontal direction of outside face of this tunnel portion and hull resistance and propulsion quality are closely related.And if the leaning angle of outside face surpasses about 15 degree, then hull resistance increases, if more than 20 degree, then the resistance increase that causes of the separation of boundary 1ayer is comparatively remarkable.And the current of the rapid speed that in tunnel portion, produces (upwelling) skim over the top of tunnel portion, move near the water surface, therefore can't the current of this rapid speed be reclaimed through screw propeller, promptly can't it be utilized as the adverse current of screw propeller.

Therefore, portion is provided with the boundary 1ayer sucking hole in the tunnel, and the water through the suction side interlayer prevents separation of boundary layer, and suppressing resistance increases.And, the hand of rotation and the position of design screw propeller, thus the current of the rapid speed that in tunnel portion, produces capable of using reclaim through screw propeller efficiently.Further, through the water of the boundary 1ayer that sucks is discharged from two, can also be as the steering gear in the navigation.

Below, with reference to this embodiment of description of drawings.Need to prove, below with model utility the needed scope of explanation that is used to reach the object of the invention is shown, with the needed scope of the explanation that relevant portion of the present invention mainly is described, can be for the part of omitting explanation with reference to known technology.

The problem of existing twin shaft stern catamaran oceangoing ship at first, is described.Figure 20 be model utility illustrate near the stern of existing twin shaft stern catamaran oceangoing ship therein near the heart along the section drawing of the state of fore-and-aft direction intercepting.Shown in figure 20, in the twin shaft stern catamaran oceangoing ship, the hull bottom 520 of hull 501 that surrounds tunnel-like recess 514 is towards quarter of a ship 513 run-off the straight sharp, so that it highly uprises.Therefore, turbulent flow takes place in the current at hull bottom 520 places, and resistance increases, and is comparatively unfavorable on propulsion quality thus.

Especially, the leaning angle X of the hull bottom 520 relative horizontal directions shown in Figure 20, when it reaches about 15 when spending, resistance begins to increase, and when leaning angle X reaches 20 degree when above, the resistance increase that the separation of boundary 1ayer causes becomes remarkable.As among Figure 20 with thicker dotted line represented, near the current the hull bottom 520 become and opposite current of water (flow) direction away from the zone of hull bottom 520, this phenomenon is called the separation of boundary 1ayer.

Figure 13 be model utility illustrate near the stern of the twin shaft stern catamaran oceangoing ship of embodiment 5 of the present invention therein near the heart along the section drawing of the state of fore-and-aft direction intercepting, Figure 14 illustrates the mode chart that the summary when observing the related twin shaft stern catamaran oceangoing ship of embodiment of the present invention 5 from the rear constitutes.Like Figure 13 and shown in Figure 14, the quarter of a ship 13 of hull 1 is provided with a pair of stern fin 11 and stern fin 12, is separately positioned on a pair of pod propulsion propelling unit 210 and the pod propulsion propelling unit 220 at the tight rear of a pair of stern fin 11 and stern fin 12.And a pair of pod propulsion propelling unit 210 and pod propulsion propelling unit 220 have screw propeller 2101 and screw propeller 2201 respectively, through the rotation generation propulsive force of this screw propeller.And, through from behind discharge orifice 71 discharge waters of explaining also being produced propulsive force.

And; When the twin shaft stern catamaran oceangoing ship of embodiment 5 of the present invention advances; In near the quarter of a ship 13 that the hull bottom 20 by stern fin 11, stern fin 12 and hull 1 surrounds the tunnel-like recess 14, produce the stronger upwelling F that the with dashed lines hollow arrow is represented among Figure 14 towards quarter of a ship 13 directions (the front direction when seeing Figure 14 (direction in front)).

Figure 13 illustrates along the state of the C1-C2 axle intercepting of Figure 14, and is shown in figure 13, and the twin shaft stern catamaran oceangoing ship of embodiment 5 of the present invention has boundary 1ayer sucking hole 70, discharge orifice 71, path 72, impeller (attraction unit) 73 and motor (attraction unit) 74.Be rotatably provided in the impeller 73 in path 72 through motor 74, form thus, can the water of boundary 1ayer be drawn into the path 72 from boundary 1ayer sucking hole 70, and be discharged to the rear from discharge orifice 71 from the current of boundary 1ayer sucking hole 70 to discharge orifice 71.And the leaning angle X that the relative horizontal direction of the outside face of tunnel-like recess 14 forms is set to more than 15 degree.

Boundary 1ayer sucking hole 70 is arranged near the inlet of tunnel-like recess 14.Therefore, near the inlet of tunnel-like recess 14 (A1 among the figure), can remove at water near the slack-off boundary 1ayer of the flow velocity of hull bottom 20 1 sides through the viscosity of water.Its result along the leaning angle X of hull bottom 20, can form the high current of velocity uniformity (A2 among the figure, A3) in tunnel-like recess 14.Thus, can prevent in tunnel-like recess 14, separation of boundary layer to take place, can suppress resistance increases.Its result can be set at the leaning angle X of the hull bottom in the tunnel-like recess 14 20 more than 15 degree, can enlarge the volume of quarter of a ship, therefore can realize the twin shaft stern catamaran oceangoing ship that stowage capacity is big, transport efficiency is high.And,, can improve the propulsive force of twin shaft stern catamaran oceangoing ship through discharge orifice 71 draining rearward from being arranged on quarter of a ship 13.

At this, boundary 1ayer sucking hole 70 is preferably near the inlet that as this embodiment, is arranged on tunnel-like recess 14, but need not be arranged on this part.As long as boundary 1ayer sucking hole 70 can play the function of the water of removing boundary 1ayer, therefore can be arranged on the position of the inlet of relative tunnel-like recess 14 near bow-side or stern-side.And boundary 1ayer sucking hole 70 can be divided into a plurality of, also can be set to multistage.

Figure 15 is the mode chart that the summary situation when hull bottom 20 sides are observed the tunnel-like recess 14 of twin shaft stern catamaran oceangoing ship of embodiment 5 of the present invention is shown.Among Figure 15, in the face of drawing, the left side is a bow-side, and the right side is a stern-side, and upside is a port side, and downside is a starboard side, and the front side is positioned at a side of below during for ship's navigation, and is inboard for being positioned at a side of top.Shown in figure 15, boundary 1ayer sucking hole 70 forms according to the width dimensions equal widths with tunnel-like recess 14 in the entrance of tunnel-like recess 14.In view of the above,, can suck the boundary 1ayer of its whole Width, therefore can suppress the increase of resistance effectively at the inlet of tunnel-like recess 14.

And the water that is sucked by boundary 1ayer sucking hole 70 can be through the impeller 73 and motor 74 in the path 72 that be arranged on that dots, and is discharged to the rear from the discharge orifice 71 of the quarter of a ship 13 that is arranged on hull 1 (referring to Figure 14), thereby improves propulsive force.

As stated, the twin shaft stern catamaran oceangoing ship of this embodiment 5 through the water from the boundary 1ayer sucking hole 70 suction side interlayers that are arranged on tunnel-like recess 14, is suppressed at the separation that boundary 1ayer takes place in the tunnel-like recess 14, increases thereby can suppress resistance.Its result can be set at the leaning angle X of the hull bottom 20 at tunnel-like recess 14 places more than 15 degree, therefore can realize the twin shaft stern catamaran oceangoing ship that stowage capacity is big, transport efficiency is high.

And, when the angle of leaning angle when 15 degree are above, if do not have the unit of attraction and boundary 1ayer sucking hole, the current in the tunnel portion slow down easily.But, through from boundary 1ayer sucking hole suction side interlayer, can control the current in the tunnel portion, it can be treated to the current that are suitable as to the adverse current of screw propeller.So, when the angle of leaning angle when 15 degree are above, can utilize the current of unserviceable in the past tunnel portion to improve the propulsive force of twin shaft stern catamaran oceangoing ship.

Embodiment 6

As implement in the mode 5 illustrated, twin shaft stern catamaran oceangoing ship of the present invention reduces resistance, improves propulsive force and transport efficiency through the water of discharging the boundary 1ayer that is sucked by the boundary 1ayer sucking hole from discharge orifice.Below, explain that discharge orifice is set to two, come to apply moment of gyration from two discharge orifice drain water amounts through changing, thereby to be used for replacing the embodiment of the small steering gear in the navigation to hull.Need to prove,, in this embodiment, omit relevant explanation for the parts of in embodiment 1, having explained.

Figure 16 is the mode chart that the summary situation when hull bottom 20 sides are observed the tunnel-like recess 14 of twin shaft stern catamaran oceangoing ship of this embodiment 6 is shown.The relation of right, left, upper and lower, front (in front), inboard (depth) is with illustrated in fig. 15 the same.Shown in figure 16; The twin shaft stern catamaran oceangoing ship of this embodiment has in the right side stern of the core when quarter of a ship 13 sides are observed and the formation that the left side stern respectively is provided with a discharge orifice; Specifically, 13 have discharge orifice 71A and discharge orifice 71B on the quarter.And, be provided with impeller 73A and impeller 73B near the discharge orifice 71A in path 72 and the discharge orifice 71B, and can change rotation, thereby change respectively from discharge orifice 71A and discharge orifice 71B drain water amount through motor 74A and motor 74B.So; Attract unit (motor 74A, impeller 73A and motor 74B, impeller 73B) through control setting at two from boundary 1ayer sucking hole 70 to discharge orifice 71A and the path 72 of discharge orifice 71B, can change from discharge orifice 71A and discharge orifice 71B drain water amount.That is, inequality through the discharge rate that makes both, to twin shaft stern catamaran oceangoing ship moment of gyration is provided, can replace the small steering gear in the navigation.In view of the above, need not the pod propulsion propelling unit is carried out steering cavitation that can suppress to cause thus and noise problem.Especially; Change from two discharge orifice 71A and 71B drain water amount through controlling two impeller 73A and 73B; For example reduce a side of water discharge rate reducing revolution, the intake quantity at boundary 1ayer sucking hole 70 places also reduces, and therefore weakens in combination with discharge rate and can improve the manoeuvre of ship effect.

At this, discharge orifice 71A and discharge orifice 71B are through providing moment of gyration to replace the small steering gear in the navigation to be used to handle boats and ships to twin shaft stern catamaran oceangoing ship.Therefore, discharge orifice 71A and discharge orifice 71B are unnecessary is arranged on from the position of quarter of a ship 13 draining rearward.But, if adopt they are arranged on the formation of quarter of a ship 13, can improve the propulsive force of twin shaft stern catamaran oceangoing ship.

For example, in the time of will being discharged to the rear from the water that boundary 1ayer sucking hole 70 sucks,, also can adopt the formation of carrying out from shipboard, hull bottom etc. even do not adopt the formation that is discharged to the rear from quarter of a ship 13.But; In order to improve the propulsion quality of boats and ships; The direction of draining (vector) is preferably towards the rear of boats and ships, prevents the separation of boundary 1ayer at tunnel-like recess 14 and reduces the effect of resistance and through being discharged to the effect that the rear advances boats and ships in order to reduce the water that resistance sucks to bring into play simultaneously.

At this, to hull the effect of moment of gyration is provided, towards the transverse drainage of relative direct of travel the time, become big.Usually; The manoeuvre of ship state of draining is that speed separation extremely slow, boundary 1ayer can not constitute the state of problem towards the side; When but the water that will attract for the separation that prevents boundary 1ayer to come in is used the manoeuvre of ship under the lower-speed state, also can adopt the formation of draining towards the side.

As stated, the discharge direction that position, quantity and water are set of discharge orifice can be considered raising effect and moment of gyration effect being provided of propulsive force and suitably sets.

For being used to change the formation of discharging the water yield, not special restriction as the scheme beyond the above-mentioned constituted mode, for example can be enumerated formation shown in Figure 17.Figure 17 is the mode chart that the summary situation when hull bottom 20 sides are observed the tunnel-like recess 14 of twin shaft stern catamaran oceangoing ship of another program of this embodiment 6 is shown.At this, right, left, upper and lower, front, inboard relation are with illustrated in fig. 15 the same.In the formation shown in figure 17; Foliated lamellar (guiding wing sheet) movable part 75, seat 75A and the seat 75B that are used for changing the current that the rotation through impeller 73 forms are arranged on path 72, have through control setting to change constituting of current in the path 72 that is formed by impeller 73 and motor 74 at the movable part 75 from the path 72 of boundary 1ayer sucking hole 70 to discharge orifice 71.As among Figure 17 with long and short dash line shown; Through changing the direction of this movable part 75; Control be divided among the path 72A of two-way towards the current of discharge orifice 71A and the current among the 72B of path towards discharge orifice 71B, can change by discharge orifice 71A and discharge orifice 71B drain water amount.Specifically, the direction of the face of the movable part 75 through changing the current in the relative path 72 can change the discharge that flows to path 72A and path 72B, thereby can change the ratio of institute's drain water amount.And the rotatable end of movable part 75 is through combining with seat 75A, can Turn Off Path 72A, and through combining with seat 75B, can Turn Off Path 72B.

At this; As the formation that changes the current in the path 72; Shown in figure 17; For can close the path 72A that branches into two-way on the way, among the 72B free routing or the path width of free routing is narrowed down, except being undertaken hinged by an end, can also enumerate the mode of valve of can Turn Off Path or regulating the width in path is set respectively in path 72A, 72B so that the rotatable tabular body of the other end constitutes the movable part 75.The mode of this control movable part 75, the mode that valve is controlled is set respectively in path 72A and 72B, an impeller 73, a motor 74 only is set, also can change the discharge rate of water and can handle the advantage of twin shaft stern catamaran oceangoing ship even have.

As stated, the twin shaft stern catamaran oceangoing ship of this embodiment respectively is provided with a discharge orifice on the quarter, two discharge orifices are set altogether, and through changing these two discharge orifice institute drain water amounts, can handle boats and ships.

But, though this embodiment adopted on the quarter 13 a plurality of discharge orifice 71A and discharge orifice 71B be set towards the rear formation, on this basis, also can a plurality of discharge orifices be set at shipboard.For example, can be provided with two on the quarter, be provided with two, four discharge orifices are set altogether at shipboard.At this moment, (1) under sail two of stern with shipboard two all carry out draining with state towards the rear; When (2) changing the orientation in the navigation,, utilize stern two, perhaps make up two of stern with shipboard two and change discharge rate according to situation; When (3) approaching etc. under the lower-speed state, close stern two, to switch two direction of shipboard and carry out discharge rate control etc., control can have various distortion from the method for the displacement that discharge orifice is discharged.

Embodiment 7

As implementing to explain in the mode 5; Twin shaft stern catamaran oceangoing ship of the present invention is through preventing to take place at tunnel-like recess 14 separation of boundary 1ayer from boundary 1ayer sucking hole 70 suction side interlayers; Through boundary 1ayer sucking hole 70 is set; Can also obtain the current with the rapid speed in the tunnel-like recess 14, promptly upwelling F (referring to Figure 14) is used for the suitable effect that improves the current of propulsive force.Therefore, explanation improves the hand of rotation and the position of screw propeller below, utilizes this upwelling F, improves the embodiment of propulsive force.Need to prove,, in this embodiment, omit relevant explanation for the parts of in embodiment 1 or 2, having explained.

Figure 18 is the mode chart that the summary when the twin shaft stern catamaran oceangoing ship of observing embodiment 7 of the present invention from the rear is shown constitutes.Shown in figure 18, the quarter of a ship 13 of hull 1 has a pair of

stern fin

11 and 12, is separately positioned on a pair of pod

propulsion propelling unit

210 and 220 at the tight rear of

stern fin

11 and 12.

Using the interval marking between the center shaft 11A of axial line 2101A and stern fin 11 of the screw propeller 2101 that x representes respectively is skew 2A, and the interval marking between the axial line 2201A of screw propeller 2201 and the center shaft 12A of stern fin 12 is skew 2B.

Shown in the arrow of Figure 18, the screw propeller 2101 of pod propulsion propelling unit 210 and the screw propeller 2201 of pod propulsion propelling unit 220 rotate along opposite sense.More specifically, when observing from the rear, pod propulsion propelling unit 2101 is along right-hand revolution, and screw propeller 2201 is along the anticlockwise direction rotation, thus the rotation of the so-called interior rotation of formation.Therefore, utilize the right half part region R 1 of the plane of revolution of the screw propeller of being represented by the formed circle of long and short dash line 2101 in the drawings, pod propulsion propelling unit 210 can be used upwelling F as adverse current.Likewise, utilize the left-half area L 2 of the plane of revolution of the screw propeller of being represented by the formed circle of long and short dash line 2201 in the drawings, pod propulsion propelling unit 220 can be used upwelling F as adverse current.At this, adverse current is meant the current of the direction opposite with the hand of rotation of screw propeller, through utilizing this adverse current, can reduce can improve its propulsive force because of screw propeller rotates the loss that water causes.

For making pod propulsion propelling unit 210 and pod propulsion propelling unit 220 be positioned at the center shaft generation out-of-position desired location of relative stern fin 11 and stern fin 12, the connecting portion that pod propulsion propelling unit 210 and pod propulsion propelling unit 220 is connected respectively to hull bottom 20 need be set.If along this connecting portion vertically is set, then because of with tunnel-like recess 14 in upwelling F rub, so become the reason of the big friction drag of generation, cause reducing propulsion coefficient.

Therefore; Shown in figure 18; The twin shaft stern catamaran oceangoing ship of this embodiment is through being connected to stern fin 11 and stern fin 12 transversely with pod propulsion propelling unit 210 and pod propulsion propelling unit 220; Thereby the connecting portion face area is diminished, realized reducing taking place the purpose of the friction drag that friction causes because of upwelling F and connecting portion.

That is to say; Pod propulsion propelling unit 210 is connected in stern fin 11 through the gondola pillar (connecting portion) 21 that is arranged on stern fin 11 inboards (being positioned at a side on stern fin 11 right sides when observing from the rear), and pod propulsion propelling unit 220 is connected in stern fin 12 through the gondola pillar (connecting portion) 22 that is arranged on stern fin 12 inboards (being positioned at a side in stern fin 12 left sides when observing from the rear).The position that makes pod propulsion propelling unit 210 that skew take place and be provided with usually than hull bottom 20 more near stern fin 11.Therefore, through pod propulsion propelling unit 210 being connected in the inboard of stern fin 11, and along the contrast that vertically is connected in hull bottom 20, gondola pillar 21 is diminished.That is, through gondola pillar 21 is connected stern fin 11 transversely, its result can set the face area of gondola pillar 21 very little.And upwelling F is between pod propulsion propelling unit 210 and stern fin 11, than between pod propulsion propelling unit 210 and hull bottom 20, flowing slowlyer.It also is like this being connected in the inboard gondola pillar 22 of stern fin 12 at the pod propulsion propelling unit 220 with opposite side.

Therefore; Through gondola pillar 21 and gondola pillar 22 being connected stern fin 11 and stern fin 12 transversely, can being provided with the face area of gondola pillar 21 and gondola pillar 22 very little and can gondola pillar 21 and gondola pillar 22 being configured in the slower part of flow velocity.In view of the above, can reduce because of the resistance that gondola pillar 21 that out-of-position pod propulsion propelling unit 210 and pod propulsion propelling unit 220 be connected to hull 1 and gondola pillar 22 and upwelling F friction cause will take place.

As stated, the twin shaft stern catamaran oceangoing ship of this embodiment 7 squints through making the screw propeller 2101 and the center shaft of screw propeller 2201 relative stern fins 11 and stern fin 12, has improved propulsion coefficient.And,, can gondola pillar 21 and the friction drag that gondola pillar 22 causes with upwelling F generation friction be minimized through gondola pillar 21 and gondola pillar 22 are arranged on stern fin 11 and stern fin 12 transversely.

Embodiment 8

Twin shaft stern catamaran oceangoing ship of the present invention as the twin shaft stern catamaran oceangoing ship that embodiment 1～3,5～7 is put down in writing, may be embodied as two modes with propulsion unit of screw propeller that are provided with, but also may be embodied as the mode with more a plurality of propulsion units.But the propulsive force with twin shaft stern catamaran oceangoing ship of three above propulsion units is to be disposed at two propulsion units between the stern fin with the part by the plane of revolution of screw propeller to obtain propulsive force be main.In this embodiment, describe having four the angle of rake twin shaft stern of pod propulsion catamaran oceangoing ships.

Figure 19 is the mode chart that the summary when the twin shaft stern catamaran oceangoing ship of observing embodiment 8 of the present invention from the rear is shown constitutes.Shown in figure 19; The twin shaft stern catamaran oceangoing ship of embodiment 8 is respectively equipped with pod propulsion propelling unit 230 and pod propulsion propelling unit 240 in the outside, tight rear of stern fin 11 and stern fin 12 the quarter of a ship 13 of the hull 1 pod propulsion propelling unit 210 inboard except the tight rear that is separately positioned on a pair of

stern fin

11 and 12 and pod propulsion propelling unit 220.The twin shaft stern catamaran oceangoing ship of embodiment 8 has in other formations, in above-mentioned embodiment, has explained, gives identical symbol, and omits explanation.

Pod propulsion propelling unit 230 is connected the outside of stern fin 11 through gondola pillar (connecting portion) 23.So, pod propulsion propelling unit 230 is connected in stern fin 11 as pod propulsion propelling unit 210, but when the stern-side of twin shaft stern catamaran oceangoing ship is observed, and is opposite from the offset direction of the center shaft 11A of stern fin 11.Therefore; When twin shaft stern catamaran oceangoing ship advances; As representing with the heavy line arrow among the figure; Pod propulsion propelling unit 230 can be utilized as adverse current with the current in stern fin 11 outsides of representing with the thick dashed line arrow among Figure 17 thus along the direction rotating screw 2301 opposite with pod propulsion propelling unit 210.

Pod propulsion propelling unit 240 is connected the outside of stern fin 12 through gondola pillar (connecting portion) 24.So, pod propulsion propelling unit 240 is connected in stern fin 12 as pod propulsion propelling unit 220, but when the stern-side of twin shaft stern catamaran oceangoing ship is observed, and is opposite from the offset direction of the center shaft 12A of stern fin 12.Therefore; When twin shaft stern catamaran oceangoing ship advances; As representing with arrow among the figure; Pod propulsion propelling unit 240 can be utilized as adverse current with the current in stern fin 12 outsides of representing with the thick dashed line arrow among Figure 17, so can improve the propulsive force of twin shaft stern catamaran oceangoing ship thus along the direction rotating screw 2401 opposite with pod propulsion propelling unit 220.

As stated; The pod propulsion propelling unit 230 and pod propulsion propelling unit 240 of the twin shaft stern catamaran oceangoing ship of this embodiment through on the basis of pod propulsion propelling unit 210 and pod propulsion propelling unit 220, setting up; Propulsive force can be further improved, the line navigation performance can be improved simultaneously.

And, through arranged outside pod propulsion propelling unit 230 and pod propulsion propelling unit 240 at stern fin 11 and stern fin 12, the direction conversion when being easy to for example approach etc. under the situation.

At this, the present invention is not limited to each above-mentioned embodiment, in the scope that does not break away from purport of the present invention, can carry out various changes and implements.And the present invention also may be embodied as the mode that the above-mentioned formation as the embodiment explanation is combined.

For example; The deviation post of screw propeller can suitably change to best place; Both can take with a navigational duty is that unit resets the deviation post of screw propeller or passes through the form that other means change the deviation post of screw propellers; Also can take on these boats and ships, to be provided with the for example means of the information such as temperature, viscosity or drinking water of seawater of real-time measurement, and be provided with according at that time situation and at any time, automatically change the form that the system of best screw propeller deviation post adjusts.

And above-mentioned embodiment only is to illustrate to be used for the example that technological thought involved in the present invention is specific, in other embodiment, also can use technological thought involved in the present invention.

Utilizability on the industry

Therefore, the present invention can be used in large ship and spitkit, and then is not only comprising the whole marine industries of ship building industry, maritime industry, and is preventing also widely entire society to be brought very huge benefit aspect the environmental protection such as global warming.

Claims

1. twin shaft stern catamaran oceangoing ship, it has two screw propellers, and this twin shaft stern catamaran oceangoing ship is characterised in that, comprising:

Drive two said screw propellers and advance the propulsion unit of said twin shaft stern catamaran oceangoing ship; With

Be arranged on two stern fins on the hull of said twin shaft stern catamaran oceangoing ship,

The set positions at the center of the axle drive shaft of two said screw propellers is that the center shaft of relative two said stern fins squints respectively.

2. twin shaft stern catamaran oceangoing ship according to claim 1 is characterized in that:

According to the hand of rotation separately of two said screw propellers, change said out-of-position direction separately.

3. twin shaft stern catamaran oceangoing ship according to claim 1 and 2 is characterized in that:

Confirm said out-of-position amplitude according to the annulus of drawing along 70～80% radiuses that distribute with the wake in the screw propeller face around the roughly maximum point of the on-cycle of a circle.

4. twin shaft stern catamaran oceangoing ship according to claim 1 and 2 is characterized in that:

The hand of rotation of the said screw propeller that twin shaft is driven is set at: when said stern-side was observed said twinscrewvessel tail binary boats and ships, the said screw propeller that is positioned at the left side was rotated in a clockwise direction, and the said screw propeller that is positioned at the right side rotates along anticlockwise direction.

5. twin shaft stern catamaran oceangoing ship according to claim 1 and 2 is characterized in that:

Reverse the rear portion of said stern fin towards the direction opposite with the hand of rotation of said screw propeller.

6. twin shaft stern catamaran oceangoing ship according to claim 1 is characterized in that:

Said propulsion unit is two pod propulsion propelling units.

7. twin shaft stern catamaran oceangoing ship according to claim 6 is characterized in that:

This twin shaft stern catamaran oceangoing ship has the connecting portion transversely that said pod propulsion propelling unit is connected to said stern fin.

8. according to claim 6 or 7 described twin shaft stern catamaran oceangoing ships, it is characterized in that:

Said pod propulsion propelling unit is a driven type.

9. twin shaft stern catamaran oceangoing ship according to claim 1 and 2 is characterized in that:

Said propulsion unit is for driving the sustainer, main engine of two said screw propellers, and said stern fin is at the protrusion that transversely has the axle drive shaft of accommodating said screw propeller of stern fin.

10. a twin shaft stern catamaran oceangoing ship has two stern fins on the quarter, and drives two screw propellers by twin shaft, it is characterized in that, comprising:

Be arranged on the boundary 1ayer sucking hole of formed tunnel portion between two said stern fins;

From said boundary 1ayer sucking hole water is attracted the attraction unit of coming in; With

The discharge orifice of the water that discharge attracts through said attraction unit to come in.

11. twin shaft stern catamaran oceangoing ship according to claim 10 is characterized in that:

Said boundary 1ayer sucking hole is arranged near the inlet portion of said tunnel portion.

12., it is characterized in that according to claim 10 or 11 described twin shaft stern catamaran oceangoing ships:

The width dimensions of said boundary 1ayer sucking hole is set at the width dimensions that is substantially equal to said tunnel portion.

13., it is characterized in that according to claim 10 or 11 described twin shaft stern catamaran oceangoing ships:

The angle of the formed leaning angle of the relative horizontal direction of outside face of said tunnel portion is more than 15 degree.

14., it is characterized in that according to claim 10 or 11 described twin shaft stern catamaran oceangoing ships:

Said discharge orifice is set to two at least, comes said twin shaft stern catamaran oceangoing ship is handled from the amount of the said water of these two said discharge orifices discharges through change.

15. twin shaft stern catamaran oceangoing ship according to claim 14 is characterized in that:

From said boundary 1ayer sucking hole to the path of said discharge orifice, being provided with two said attraction unit, change from two said discharge orifice drain water amounts through controlling these two said attraction unit.

16. twin shaft stern catamaran oceangoing ship according to claim 14 is characterized in that:

From said boundary 1ayer sucking hole to the path of said discharge orifice, being provided with the movable part that is used to change the current that form through said attraction unit,, change from two said discharge orifice drain water amounts through controlling this movable part.