Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H1/00—Propulsive elements directly acting on water
  • B63H1/30—Propulsive elements directly acting on water of non-rotary type
  • B63H1/32—Flaps, pistons, or the like, reciprocating in propulsive direction
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63H—MARINE PROPULSION OR STEERING
  • B63H1/00—Propulsive elements directly acting on water
  • B63H1/30—Propulsive elements directly acting on water of non-rotary type
  • B63H1/36—Propulsive elements directly acting on water of non-rotary type swinging sideways, e.g. fishtail type

Definitions

• the present invention relates to a propulsion system for a maritime vessel wherein the employed means for propulsion includes flapping, translating or oscillating foils or fins.
• the present invention relates to a maritime vessel propelled by a mechanism incorporating transversely translating propulsive means.
• the mechanism comprises:
• - water engaging propulsive means having an upper portion facing a portion of the hull and a lower portion extending away from the hull, an axis of rotation oriented substantially normal to a part of the hull which lies substantially above the propulsive means;
• the present invention is an important practical element to easily realize efficient and operative flapping propulsion based on the combination of one periodical translating movement and possibly one periodical rotational movement of one or several fins under the ship.
• the oscillating motion of a fishtail can be simulated and generated either by rotation of a fin, or, as is the case with sea-mammals and tuna-related fish, by a combination of at least one periodical translation and one periodical rotation of the caudal fin.
• the propulsive means e.g. propellers, jets, ducted propellers or pump jets etc.
• the propulsive means are rotating about their own axis.
• the propellers are rotating at about 50-500 rpm.
• the propellers are carefully designed for their particular application.
• US patent no 5,401 ,196, published March 28, 1995 disclose a propulsion system employing flapping foils.
• the patent which teaches a system utilizing at least one foil, discloses a propulsive system wherein a foil is oscillated in a direction transverse to the vessel's sailing direction and is rotationally oscillated about a vertical axis.
• the propulsive system is built up from a plurality of foils which are oscillated out of phase resulting in the propulsive elements thrust in a direction transverse to the sailing direction is insignificant.
• half the foils are preferably oscillated 180° out of phase with the other half of the foils.
• the foils are oscillated 120° out of phase with each other.
• FIGS 4A, 4B, 5A, 5B & 5C illustrate an embodiment for a foil propulsion system in accordance with the US patent.
• the propulsive system is build up from two foils (10), each connected via a shaft (34), through a slit (36) in the aft section of the hull (30) to a table (40).
• each table (40) has two or more wheels or rollers (42) mounted to the forward underside and to the rear underside, in which the wheels or rollers ride in corresponding tracks (44) mounted to hull (32).
• the tables (40) and the foils (10) attached thereto are thus free to move both directions along one axis (38), and are fixed from movement in any other direction.
• the mechanism according to the US patent is working through a number of slits (36) established in the hull (32), each transverse to the vessels forward sailing direction, and the extension of the slits (36) exceeding the transverse motion of the foils.
• the fins are also rotating under power around axes placed such that rotation substantially affects the angle of the foil with the direction of motion of the ship. All disclosed axes of rotation are established as substantially vertical axes.
• the above prior art document discloses the hull provided with a horizontal and transverse slit at the location where the fin axles crosses the shell of the hull. While such a configuration is possible, it would cause significant drag when located close to, or even below, the waterline. The drag would originate form the slits themselves or from the so chosen stern shape.
• the sternline includes a horizontal longitudinal section under water, with fins pitching about a vertical axis, the streamlines of flow around the hull would be disturbed due to the abrupt curvature of the longitudinal sternline section, and the boundary layer would be large at the location of the fins, thereby causing operation with poor efficiency.
• the longitudinal sternline is not sloped or inclined enough, the transom of the ship would be at least partially submerged in full loading conditions, causing higher hull drag and low total efficiency.
• Prior art propulsive systems incorporating propulsion by one or more rotating propellers suffers under the fact that the fairly large propeller, in order to obtain optimum operating conditions, has to be immerged under all operating conditions.
• a vessel with a design draught of 9,0 m, and incorporating a propeller with a diameter of abt. 6,8 m will be able to obtain optimum working conditions only in draughts in excess of abt. 7 m.
• WO 03/026954 A1 published April 3, 2003 (Inocean) suggests a system utilizing a sinusoidal pattern of movement for propulsion or energy recovery.
• the system comprises a plurality of rigid hull elements arranged in a row and rotatable attached to one another for rotation about parallel axes of rotation across the longitudinal dimension of the row of hull elements.
• the system further comprises movement devices for rotating the hull elements relative to one another or movement devices for recovery of energy as a result of rotating the hull elements relative to one another.
• WO 2006/038808 A1 published April 13, 2006 (Clavis Biopropulsion) suggests a device comprising at least one transversely translating fin.
• the device encompasses actuating and drive means allowing substantially free oscillating motion of the fin.
• the device operates by means of an impulse, established by drive means, every so many cycles and spring are used to store the pulsating energy provided by the drive means.
• the solution is to construct a maritime vessel wherein a part of the hull, from where the propulsive means extend is sloped with respect to a base line of the hull.
• the means for rotating the propulsive means constitutes means operating independently from the source of propulsive power.
• the means for rotating the propulsive means constitutes at least one motor or ram powered by electrical power, air or a viscous fluid.
• the oscillating or translating motion of the propulsive means is exclusively powered from the source of propulsive power.
• the hull is substantially flat, locally or not, on a part of a transverse section of the hull from where the means for propulsion extend or protrude.
• a curvature of the hull is substantially arc- shaped on a part of a transversal and/or longitudinal section around the location where the means for propulsion extend or protrude.
• a lower part of the means for propulsion is in any operating loading condition located above the baseline of the hull.
• an upper part of the means for propulsion may in any operating loading condition be located below the waterline.
• the means for rotating said propulsive means is controlled such that an optimum or desired angle of attack between the propulsive means and the water through which the vessel is propelled is obtained.
• the means for rotating the propulsive means controls and/or rotates the propulsive means in order to compensate for various patterns of translational movement of the propulsive means.
• control and/or rotation of said propulsive means constitutes an adaptive system wherein the rotation of the propulsive means is adapted to requested thrust vectors and/or optimized in order to achieve optimum, i.e. lowest possible, fuel consumption.
• Figure 1 shows a principal and longitudinal sectional view of a ship incorporating translating or oscillating means for propulsion according to the present invention.
• Figure 2 shows an enlarged principal and sectional side view of a system incorporating translating or oscillating means for propulsion according to the present invention.
• Figure 3 shows a principal transversal section of a system incorporating translating or oscillating means for propulsion according to the present invention.
• Figure 4 shows a principal and sectional top view of a system incorporating translating or oscillating means for propulsion according to the present invention.
• the oscillating or translating fin propulsion according to the present invention offers improved efficiency over a broad range of draughts and speeds.
• a maritime vessel is provided propulsive means 2, such as fins or foils, arranged with an upper part 1 travelling or translating across and below the shell of the hull 3 under or near the waterline 4 of any normal operational loading condition of the vessel, and the opposite lower part 5 extending into a depth of the water.
• propulsive means 2 such as fins or foils
• the propulsive means 2 such as fins or foils, must encompass sufficient water engaging surface area in order to obtain sufficient water engaging area.
• the hull form, and thereby the transversally sloped shape of the hull 3 incl. form of the propulsive means 2 are determined from a number of hydrostatical parameters, all of which being optimized in order to obtain the lowest possible towing resistance and best possible propulsive efficiency while maintaining optimal sea keeping and stability properties etc.
• the vessel may be constructed with its hull 3 sloping longitudinally upwards towards the aft part of the vessel, also at the locations from where the axles 7 of the means for propulsion 2 protrude from the hull 3.
• the axes 8, about which the axles 7 pivot or rotate, are oriented substantially normal to the hull 3, at the locations from where the axles 7 of the means for propulsion 2 protrude from the hull 3. Therefore, the pivot axis 8 of the means for propulsion 2 is positively inclined meaning that an upper part of the means for propulsion 2 is located forwards the lower part of the means for propulsion 2.
• the vessel may be provided with inclined fins or foils.
• Inclining the means for propulsion 2 allows the designer of the vessel to design the propulsive means 2 with sufficient water engaging area although the means for propulsion 2 are protruding through the hull from positions located near or below the waterline 4 of all normal operating loading conditions of the vessel, while not protruding below the baseline of the ship.
• a substantially flat section around the area of protrusion of the means for propulsion 2 accommodates or facilitates the provision of means for sealing 9.
• the means 10 for rotating the propulsive means 2 may constitute a least one motor or ram, which may suitable by hydraulically or pneumatically powered, or powered by electrical power, air or a viscous fluid.
• the means 10 for rotating the propulsive means may be controlled by means of an internal or external processor, such as a PC or equivalent (not shown). Further, the processor or PC may be able to control the means 10 for rotating the propulsive means such that any desired translational pattern of movement of the propulsive means 2 is optimized with respect to fuel efficiency and desired directions of thrust.
• an internal or external processor such as a PC or equivalent (not shown).
• the processor or PC may be able to control the means 10 for rotating the propulsive means such that any desired translational pattern of movement of the propulsive means 2 is optimized with respect to fuel efficiency and desired directions of thrust.
• the rotation of the propulsive means 2 may also be performed by pure mechanical links.
• Such links or linkage system may either control the propulsive means 2 jointly or independently.
• the link or link system may be connected directly to the hull 3, or to other mechanical means assisting the generation of the desired motion or rotation of the propulsive means 2.
• the means 10 for rotating the propulsive means 2 may preferably be able to rotate the propulsive means 2 about their axis of rotation 8 independently from the heave motion of the means for propulsion 2, and further, the means for rotating the propulsive means 2 may constitute at least one separate drive 10 per propulsive system 11.
• the means 10 for rotating the propulsive means 2 may preferably control the angle of the propulsive means 2 such that an optimum or desired angle of attack between the propulsive means and the fluid is obtained.
• the means 10 for rotating the propulsive means 2 may control and/or rotate the propulsive means 2 in order to compensate for various patterns of translational movement of the propulsive means 2, e.g. sinusoidal or non- sinusoidal movement patterns. Further, the control and/or rotation of the propulsive means 2 may constitute an adaptive system wherein the rotation of the propulsive means 2 is adapted to requested thrust vectors and/or optimized in order to achieve optimum, i.e. lowest possible, fuel consumption.
• the transversal cross section of figure 3, positioned substantially through the section where the means for propulsion 2 translates, is, as per the above, preferably substantially flat in order to avoid induced drag through leakage from the pressure side to the suction of the means for propulsion caused by gaps between the upper part of the means for propulsion 1 and the hull 3.
• the oscillating or translating motion of the propulsive means 2 may be powered exclusively from the source of propulsive power.
• the propulsive power may originate from one or more engines or prime movers, e.g. a slow speed or medium speed engine. Further, it will be possible to realize the invention utilizing any kind of turbines powered by gas, steam or even nuclear energy.
• the propulsive means 2 may constitute fins or foils suitable for producing thrust when operated as per the introductory part of this specification.
• the propulsive system 11 may be arranged as port and starboard systems being offset in a longitudinal direction. It will be possible to construct a vessel with the systems being juxtaposed or being placed longitudinally one in front of the other, either totally or partially.
• the propulsion mechanism according to the present invention is not in any way limited to one configuration above another configuration.
• the propulsive system 11 may be arranged or provided in the hull 3 of a maritime vessel under several configurations, some of which are:
• the propulsion mechanism according to the present invention is not in any way limited to one configuration above another configuration.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• Ocean & Marine Engineering (AREA)
• Other Liquid Machine Or Engine Such As Wave Power Use (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

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Family Applications (1)

Country Status (2)

Family Cites Families (4)

• 2008
  • 2008-12-09 WO PCT/EP2008/067126 patent/WO2009074579A1/en active Application Filing
  • 2008-12-09 EP EP08859420A patent/EP2225148A1/de not_active Withdrawn

Non-Patent Citations (1)

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