WO2019235281A1

WO2019235281A1 - Ship with little wind-pressure resistance

Info

Publication number: WO2019235281A1
Application number: PCT/JP2019/020880
Authority: WO
Inventors: 田中　良和; 豪谷口; 校優木村; 剛大池田; 則道浅沼
Original assignee: 商船三井テクノトレード株式会社; 株式会社三井造船昭島研究所; 株式会社商船三井
Priority date: 2018-06-04
Filing date: 2019-05-27
Publication date: 2019-12-12
Also published as: KR102438509B1; JP2019209821A; CN112272637B; CN112272637A; JP6687673B2; KR20210006354A

Abstract

The present invention is configured such that, in a horizontal cross-section Sh(z) of above-water structures 2, 20, having a stern-side first range Rx1 and a vertical first range Rz1, a fan-shaped region Rα denotes the space between a first inclined line L1 that extends at a first angle α1 of 50° with respect to the bow direction Lc in the longitudinal direction X, and a second inclined line L2 that extends at a second angle α2 of 80°. A virtual point P2(z) of the pivot of the fan-shaped region Rα is positioned such that, when the virtual point P2(z) is moved forward or backward along a hull center line Lc, 50-100% of the length of a contour Ls(Z) of the horizontal cross-section Sh(z) falls within the fan-shaped region Rα. According to this configuration, a ship with little wind-pressure resistance can be provided, thereby reducing the effects of cross-head winds, generating lift in the above-water structures constituted by a ship hull or from an upper structure and loaded freight, making it possible to obtain thrust from the lift component in the longitudinal direction of the hull, and enabling improved propulsion performance of the ship.

Description

Ship with low wind pressure resistance

The present invention particularly relates to a ship having a low wind pressure resistance against an oblique head wind, and more particularly to a ship having a reduced wind pressure resistance against an oblique head wind by devising the shape of the stern side of an upper structure such as a bridge or a residential area.

Most merchant vessels traveling on the water have reduced drag by devising the shape of the hull below the surface of the ship and improved propulsion performance due to the relationship between the hull, propeller and rudder. Regarding resistance reduction in wave-making resistance, breaking wave resistance, and reflected wave, resistance reduction is achieved by devising bow shape and stern shape.

On the other hand, regarding the resistance by air on the water surface, there is a demand for improvement in air resistance, that is, wind pressure resistance, and various efforts have been made. In particular, car carriers with large psoriasis and a large wind pressure area (automobile dedicated ships), container ships that increase the wind pressure area due to loading of cargo, and passenger ships with large superstructures have a large wind pressure area on the water surface. There is great expectation because it is easily affected and the reduction in wind pressure resistance leads to energy saving.

In this connection, for example, as described in Japanese Patent Application Laid-Open No. 2011-57052, the shape of the stern side of the upper structure provided on the upper deck, or the stern side of the hull on the water surface In the shape of each cross section parallel to the water surface in the range of at least 0% to 50% of the vertical structure of the water surface structure, the maximum width B Compared to an isosceles trapezoid with the rearmost part at the stern side of the lower side of the base, the lower side length B1 being 0.9 × B, the base angle θ1 being 40 deg to 80 deg, and the upper side length B2 being 0.5 × B The outer side of the isosceles triangle with the stern side rearmost portion of the maximum width B as the base, the base length B3 is 1.2 × B, and the base angle θ2 is 40 deg to 80 deg. A ship with low wind pressure resistance formed to enter the area Proposed.

In this ship with low wind pressure resistance, the wind pressure area on the surface of the water is relatively large, and it is possible to reduce the influence of wind pressure on car carriers, container ships, passenger ships, etc. that are easily affected by wind pressure, and improve the ship's operational performance. However, it has proposed a shape that prevents outflow vortices such as stagnant vortices and Karman vortices that occur in the dead water region behind the structures on the surface of the water, mainly for headwinds from the front.

On the other hand, as described in Japanese Patent Application No. 2014-501194, for example, aerodynamic lift in the traveling direction of the ship is generated by relative wind so that the hull functions as a sail. In addition, there is proposed a hull whose cross section is perpendicular to the front and rear direction of the hull by cutting off the trailing edge on the stern side with a symmetrical NASA aerial wing as the shape of the hull on the water surface. Yes. The hull discloses the results of a wind tunnel test in which a wind component acting in the direction of ship movement was obtained in a wind sector of about 13 to 39 degrees.

In this way, it is important to reduce the wind pressure resistance not only against the head wind in the direction of travel of the ship but also against the head wind obliquely depending on the route the ship navigates and the weather conditions at the time of navigation. It has become.

Japanese Patent Application No. 2011-57052 Japanese Patent Application No. 2014-501194

The inventors of the present invention said that the ship's own ship speed and the wind speed of the natural wind are approximately the same during the navigation of the ship, and there is a high probability that the wind will be diagonally headwind when considered in the relative wind direction. Obtained knowledge. And by the results of wind tunnel experiments with diagonal headwinds, etc., especially the shape at the stern has a great influence on the wind pressure resistance, and by devising the shape of the outer structure of the ship's surface structure, without providing a sail in particular They also learned that thrust can be obtained when the wind is diagonally headwind.

The present invention has been made in view of the above situation, and the purpose thereof is relatively large in the wind pressure area on the water surface, and is easily affected by wind pressure in an automobile carrier ship, a passenger ship, a container ship, a wood carrier ship, etc. In addition to reducing the effects of slant headwinds, it is possible to generate lift from the surface structure formed by the hull or superstructure and cargo loaded 30 such as containers, and to obtain thrust from the longitudinal components of this hull An object of the present invention is to provide a ship with low wind pressure resistance that can improve the propulsion performance of the ship.

The ship with low wind pressure resistance according to the present invention for achieving the above object is a ship having a cruising speed of 0.13 to 0.30 in terms of fluid number, and an upper part provided on the hull on the water surface or on the upper deck. In at least one water surface structure of the structure, a point on the hull center line at the rearmost portion of the stern side of the maximum width of the water surface structure is defined as a first position, and the space between the first position and the last tail of the hull The first range on the stern side of the structure on the water surface is defined as a first range on the stern side, and a range of 50% or more and 100% or less in an arbitrary continuous portion in the vertical direction of the structure on the water surface is defined as a first range in the vertical direction. And in each horizontal cross section parallel to the water surface in the upper and lower first range, a line extending at a first angle from a virtual point on the hull center line with respect to the bow direction in the front-rear direction of the hull is defined as a first inclined line, and from the virtual point Second angle with respect to the bow direction of the hull The extending line is a second inclined line, the first angle is 50 degrees (corresponding to θ = 40 degrees), the second angle is 80 degrees (corresponding to θ = 10 degrees), and the first inclined line and the When the imaginary point is moved on the hull center line with the second inclined line as a sector area, and the sector area is moved in the front-rear direction of the hull, 50% of the length of the outline of the horizontal section The position of the imaginary point is such that an outline having a length of 100% or less enters the sector area.

The Froude number Fn is Fn = V / (Lpp × g) where V (m / s) is the navigation speed, Lpp (m) is the length between perpendiculars, and g (m / s ² ) is the gravitational acceleration. ^1/2 . Here, the reason why the Froude number Fn of the ship targeted by the present invention is set to 0.13 to 0.30 is that the Froude number Fn is larger than 0.30. This is to distinguish the stealth technique from the stealth cover, because the entire hull may be covered and covered.

According to this configuration, the stern shape of the hull on the water surface or at least one water surface structure of the upper structure provided on the upper deck has an angle α on one side of 40 degrees (degrees) to 80 degrees. By making the stern flow similar to the flow at the rear end of the wing as a relatively wide open V-shape, it is possible to make a shape that can generate lift when the wind is diagonally headwind.

Due to this shape, the wind at the stern is improved when the wind is diagonally headed, the flow of the structure on the surface of the water is smooth, and the portion of the structure on the surface of the water exerts the function of the wing to increase the lift. The thrust of the ship can be obtained by the component of the lift in the longitudinal direction of the hull. The generation of lift and thrust has been confirmed by the results of wind tunnel experiments.
Further, due to the obtuse stern side shape of the structure on the water surface, if the vessels have the same overall length, there is also an advantage that the volume increases and the load capacity increases accordingly.

In the ship with low wind pressure resistance, in the shape of each horizontal cross section in the first vertical range (Rz1), the width of the unevenness is the maximum width of the structure on the water surface. When formed with a smooth curved portion that is 5% or less, or a straight portion where the width of the unevenness is 5% or less of the maximum width of the structure on the water surface, or a combination of both, as follows Effects can be obtained.

According to this configuration, it is possible to suppress the occurrence of a large vortex by causing separation in the flow at the curved portion or the straight portion by forming the smooth curved shape or the straight shape with less unevenness. Can do.

In the above-mentioned ship with low wind pressure resistance, the side wall portion that forms the stern side of the structure on the water surface is 30 degrees or more and 90 degrees or less with respect to the horizontal plane in the first range on the stern side and the first range on the upper and lower sides. If it is formed to have an inclination angle, the following effects can be obtained.

According to this configuration, the corner portion between the stern side upper surface and the stern side wall portion forming the stern side of the structure on the water surface by inclining the side wall portion on the stern side at 30 degrees or more and 90 degrees or less with respect to the horizontal plane. The eddy current generated by the Furthermore, by providing cornering or rounding at the corner between the stern side upper surface and the ship side wall, eddy current can be more effectively suppressed.

In the above-described ship with low wind pressure resistance, when the upper structure is a water surface structure, 50% of the side wall portion of the upper structure in each horizontal section in the first range on the stern side and the first range in the upper and lower sides. % Of the straight line with respect to the center line of the hull, and the average value in the first vertical range with respect to the vertical direction of the first hull is defined as the first average angle αm, and the side wall of the hull below the superstructure 20% or more of the stern side from the front surface of the superstructure in the section is formed with a straight line, and the average value in the range of the freeboard of the hull in the vertical direction of the third angle with respect to the center line of the hull is the third average angle θm When the angle γ1 is 5 degrees and the relationship between the first average angle αm and the third average angle θm is (αm−γ1) ≦ θm ≦ (αm + γ1), the following effects are obtained. Can be demonstrated.

According to this configuration, there is less flow in the vertical direction between the upper structure on the stern side and the freeboard of the hull, and the wing shape of each of the upper structure and the hull is maintained by maintaining a planar flow. The rear end effect can be maintained, and the propulsion performance due to the generation of lift can be improved while suppressing an increase in wind pressure resistance of the entire ship in an oblique wind.

In the above-mentioned ship with low wind pressure resistance, when the hull is a structure on the water surface, 30% or more of the stern side of the structure on the water surface is a straight line in the first range on the stern side and the first range on the upper and lower sides. When the average value in the range of the hull of the hull in the vertical direction of the third angle with respect to the hull centerline is the third average angle θm, the angle γ2 is 20 degrees, and θ1 is 50 degrees, The third average angle θm has a relationship of (θ1−γ2) ≦ θm ≦ (θ1 + γ2).

According to this configuration, even in a ship in which an upper structure such as a container ship is arranged forward or in the hull longitudinal direction, the stern shape of the hull exhibits the wing shape rear end effect, While suppressing an increase in wind pressure resistance of the entire ship in the wind, it is possible to improve the propulsion performance resulting from the generation of lift.

Also, depending on the way the container or the like is placed on the upper deck of the loaded cargo 30, the overall shape of the loaded cargo can be matched to the stern shape of the hull or similar, so that In addition to the rear end effect of the wing shape, the rear end effect of the wing shape can be exhibited also in the shape of the cargo on the upper deck as a whole.

According to the ship with low wind pressure resistance of the present invention, the wind pressure area on the surface of the water is relatively large, and in the automobile carrier ship, passenger ship, container ship, timber carrier ship, etc. that are easily affected by the wind pressure, the influence of the diagonally headwind is reduced. To improve the propulsion performance of the ship by generating lift from the surface structure formed by the hull or superstructure and loaded cargo such as containers, and obtaining thrust from the longitudinal components of this hull Can be obtained, and the propulsion performance of the ship can be improved. As a result, fuel consumption can be improved and energy saving can be achieved.

FIG. 1 is a view of a ship according to the first embodiment of the present invention as seen from the rear above a diagonal port. FIG. 2 is a side view of the rear side of the hull as a structure on the water surface in the ship of FIG. FIG. 3 is a plan view showing a stern side shape of a horizontal section of a hull as a structure on the water surface in the ship of FIG. FIG. 4 is a right side view of the ship according to the second embodiment of the present invention. FIG. 5 is a view of the upper structure as the water surface structure in the ship of FIG. FIG. 6 is a right side view of the stern portion of the ship of FIG. FIG. 7 is a horizontal sectional view of the stern portion of the ship of FIG. FIG. 8 is a schematic plan view showing a relationship in angle between the rear side wall portion of the upper structure of the ship of FIG. 4 and the side wall portion of the hull in plan view. FIG. 9 is a right side view of the ship according to the third embodiment of the present invention. FIG. 10 is a schematic plan view showing a relationship of angles in a plan view of the side wall portion of the hull in the ship of FIG.

Hereinafter, an embodiment of a ship with low wind pressure resistance according to the present invention will be described with reference to the drawings. Here, in the first embodiment, an explanation will be given taking an automobile carrier (automobile ship) as an example, and in the second embodiment, a cargo having an upper structure of a residential area and a bridge provided above the upper deck. The explanation is given by taking a ship as an example. However, the present invention can be applied not only to automobile carriers and cargo ships but also to other ships such as passenger ships. In order to exclude ships that cover and cover the hull for stealth technology, the number of fluids Fn related to the ship's navigational speed V is 0.13 to 0.30. Note that the bow perpendicular F.R. P. And Stern perpendicular line A. P. Is the distance between perpendiculars Lpp.

First, a ship (hereinafter referred to as a ship) with low wind pressure resistance according to the first embodiment will be described. As shown in FIGS. 1 to 3, the ship 1 of the first embodiment is an example of an automobile carrier ship. In order to fix and transport a car from the bow of the hull 2 to the stern, The upper deck 3, which is the uppermost deck, has a plurality of decks, and is provided with a mast 4 and a chimney 5, but is not provided with a bridge such as a bridge or a residential area. In this ship 1, the bridge and the residential area are provided below the upper deck 3, and nothing projecting as much as possible above the upper deck 3 is provided to reduce wind pressure resistance. For example, the bridge is provided in the bow portion that is well-viewed below the upper deck 3, and the residential area is provided on the stern side near the engine room with the engine.

Also, below the water surface, a bow valve 2a is provided on the bow side, and a propeller 6 and a rudder 7 are provided on the stern side. In the ship 1 of FIG. 1, a 1-axis 1 rudder is used, but the present invention is not limited to this, and a 2-axis 2-rudder multi-axis ship or the like may be used.

In this configuration, an inclined surface 3a that faces upward from the upper end of the front edge of the bow toward the upper deck 3 is formed at the bow. The inclined surface 3a is formed so that the upward angle with respect to the horizontal plane is 20 degrees (degrees) to 60 degrees, and preferably 38 degrees. As a result, when the wind flow flows from the upper end of the bow front edge toward the upper deck 3, the separation of the upper deck 3 and the generation of vortices are suppressed to reduce the wind pressure resistance.

A notch 9 is provided at the corner formed by the upper deck 3 and the side 8 of the hull 2 over the entire length from the bow to the stern. As shown in FIG. 1, this notch 9 is 5 to 20% of the freeboard fb in the ballast state obtained by subtracting the ballast draft db from the depth D from the upper deck to the bottom of the ship (the keel line) in the center of the hull. It is formed having a depth ds and a width bs. For example, it is formed by cutting out into a square shape with a width of one or two cars to be loaded.

The notch step portion 9 suppresses the separation and vortex generation at the corner portion connecting the upper deck 3 and the heel side portion 8 with respect to the oblique wind, thereby reducing the resistance, lateral force, and yaw moment due to the wind pressure. . The cut-out step 9 has a great effect when it is provided over almost the entire length from the bow to the stern, but it may be provided over a range from the bow to almost the center of the hull.

Moreover, in the structure of FIG. 1, the opening part for the lampway for performing the cargo handling of a motor vehicle, and its door 10 are provided in the stern of the part on the water surface (structure on water surface) of the side part 8 of the hull 2. . Moreover, you may provide the opening part for the lampway for performing the cargo handling of a motor vehicle, and its door also in the side part 8 near the center part of the hull 2. FIG.

As shown in FIGS. 1 to 3, in the above-surface structure 2 that is a hull on the water surface, a point on the hull center line Lc at the stern side rearmost portion of the maximum width Bmax of the hull 2 is defined as a first position P1. The stern side first range Rx1 is defined between the first position P1 and the rearmost Pa of the hull 2. Further, a range of 50% or more and 100% or less, preferably 40% or more and 100% or less, in an arbitrary continuous portion in the vertical direction of the water surface structure 2 is defined as a first vertical range Rz1. The stern-side first range Rx1 of the water surface structure 2 and the first vertical range Rz1 are defined as the stern specific range Sa1 (cross-hatched portion in FIGS. 1 and 2). Note that the entire vertical range is the bottom of the water surface, up to the top of the hull 2 excluding the mast 4 and chimney 5, and up to the top of the upper structure (not shown). To do.

And in each horizontal cross section Sh (z) parallel to the water surface in the stern specific range Sa1, with respect to the bow direction (plus X direction) in the longitudinal direction X of the hull 2 from the virtual point P2 (z) on the hull center line Lc. The line extending at the first angle α1 is defined as the first inclined line L1, and the line extending at the second angle α2 with respect to the bow direction (plus X direction) in the front-rear direction X of the hull 2 from the virtual point P2 (z) The inclined line L2. Further, here, the first angle α1 is 50 degrees (preferably 55 degrees), and the second angle α2 is 80 degrees, preferably 65 degrees. Further, a space between the first inclined line L1 and the second inclined line L2 is defined as a sector area Rα (z).

Under the above conditions, when the virtual point P2 (z) is moved on the hull center line Lc and the sector region Rα (z) is moved in the longitudinal direction X of the hull, the horizontal section Sh (z) A virtual line in which an external line Ls (z) having a length of 50% or more and 100% or less, preferably 60% or more and 100% or less of the length of the external line Ls (z) enters the sector region Rα (z). It is configured so that the position of the point P2 (z) exists. In other words, when the virtual point P2 (z) is provided at an appropriate position on the hull center line Lc, the horizontal cross section Sh (z) is located inside the sector region Rα (z) having the virtual point P2 (z) as a vertex. The outer shape Ls (z) has a length of 50% to 100%, preferably 60% to 100%.

According to this configuration, the stern shape of the structure on the surface of the hull 2 on the surface of the water is a relatively wide open V having an angle α on one side of 40 degrees (degrees) to 80 degrees, preferably 55 degrees to 65 degrees. It can be a letter shape. With this stern shape, the flow at the stern is similar to the flow at the rear end of the wing, and lift can be generated in the same direction as the wing when the wind is diagonally headed.

In other words, the hull 2 having the stern shape improves the draft of the wind at the stern when the wind is diagonally headwind, and the flow toward the rear of the water surface structure 2 is smooth. The function of the wing can be demonstrated to generate lift. The thrust of the ship 1 can be obtained by the component in the longitudinal direction X of the hull 2 of this lift. The generation of lift and thrust has been confirmed by the results of wind tunnel experiments.

There is almost no superstructure that stands on the exposed deck like this car carrier or passenger ship, or it is very small, and the part on the surface of the water is such that the hull 2 extends upward from the surface. Since the hull 2 from the bow to the stern has a shape similar to the wing shape, the stern shape has substantially the same function as the rear end of the wing. The generated lift can be increased, and thrust can be obtained from this lift.

Further, according to this configuration, since the wind escape on the stern side of the hull 2 is improved with respect to the oblique wind, the generation of vortex in the stern part of the hull 2 is reduced, and the hull side due to the wind in this part is reduced. The wind force in the direction Y can be reduced, and the turning moment due to the wind acting on the hull 2 can be reduced. As a result, the rudder angle for canceling the turning moment can be reduced, the propulsion efficiency can be improved from this aspect, and the maneuverability can also be improved.

Also, due to the obtuse stern side shape of the hull 2, if the vessels have the same overall length, there is an advantage that the volume increases and the loading capacity increases accordingly.

Further, the side wall 8 (side portion) of the stern specific range Sa1 that forms the stern side of the structure 2 on the water surface has a width of unevenness in the shape of each horizontal cross section Sh (z) of the upper and lower first range Rz1. It is preferable to form a smooth curved portion having a maximum width Bmax of 5% or less, a straight portion having an uneven width of 5% or less of the maximum width Bmax of the hull 2, or a combination of both. By adopting this configuration, it is possible to suppress the occurrence of a large vortex due to separation in the flow at the curved portion or the straight portion.

Further, the side wall portion 8 forming the stern side of the structure 2 on the water surface has an inclination angle β of 30 degrees or more and 90 degrees or less with respect to the horizontal plane in the stern side first range Rx1 and the first vertical range Rz1. If it forms in this, the eddy current which arises in the corner | angular part of the upper deck 3 and the side wall part 8 of the stern side upper surface which forms the stern side of the structure 2 on the water surface can be suppressed. In addition, if this side wall part 8 is formed in the curved surface shape where the whole on the water surface or a part on the upper side protrudes outward, the air flow that has flowed above the water surface structure 2 (the upper surface of the deck or the bridge, etc.) Further, it may be lowered along the curved surface of the side wall portion 8 so that an increase in resistance due to generation of a vortex or the like can be suppressed. In this case, the angle between the tangent surface at each point on the curved surface and the horizontal plane is defined as an inclination angle β.

If the inclination angle β is smaller than 30 degrees, the lower part of the stern side part will extend greatly in the stern direction, and if it is larger than 90 degrees, it becomes impractical. Furthermore, eddy currents can be more effectively suppressed by providing chamfering or rounding at the corners of the upper deck 3 and the side wall 8.

Next, a ship with a low wind pressure resistance (hereinafter referred to as a ship) according to the second embodiment will be described. As shown in FIGS. 4 to 8, the ship 1A of the second embodiment is an example of a cargo ship (in this case, a bulker), and has a bridge 21 and a residential area on the upper deck 3 of the stern part. This is a stern funnel ship in which an upper structure 20 having 22 is arranged. As an example of this cargo ship, a ship having a stern living area such as a bulker, a tanker, and a general cargo ship is given as an example. A mast 4 and a chimney 5 are provided on the upper surface of the upper structure 20, and a navigation wing (dodger) 21 a, which is a portion projecting to the ship side with a part of the deck of the navigation bridge on both sides of the bridge 21. Is provided.

As shown in FIGS. 4 to 8, in the water surface structure 20 that is the upper structure 20 provided on the upper deck 3, on the hull center line Lc at the stern side rearmost portion of the maximum width Bmax of the upper structure 20. A point is defined as a first position P1, and a stern side first range Rx1 is defined between the first position P1 and the last tail Pa of the hull 2. Moreover, the range of 50% or more and 100% or less, preferably 40% or more and 100% or less in the vertical direction of the water surface structure 20 is defined as the first vertical range Rz1. The entire range in the vertical direction is from the lower end of the upper structure 20, that is, from the upper surface of the upper deck 3 to the uppermost part of the upper structure 20 excluding the mast 4 and the chimney 5.

The stern side first range Rx1 of the water surface structure 20 and the first vertical range Rz1 are defined as the stern specific range Sa1 (cross-hatched portion in FIGS. 4 to 6). The horizontal cross section Sh (z) parallel to the water surface in the stern specific range Sa1 is the first to the bow direction (plus X direction) in the front-rear direction X of the hull 2 from the virtual point P2 (z) on the hull center line Lc. A line extending at one angle α1 is defined as a first inclined line L1, and a line extending at a second angle α2 with respect to the bow direction (plus X direction) in the longitudinal direction X of the hull 2 from the virtual point P2 (z) is defined as a second inclined line. Let L2. Further, here, the first angle α1 is 50 degrees (preferably 55 degrees), and the second angle α2 is 80 degrees, preferably 65 degrees. Further, a space between the first inclined line L1 and the second inclined line L2 is defined as a sector area Rα (z).

When the virtual point P2 (z) is moved on the hull center line Lc and the fan-shaped region Rα (z) is moved in the front-rear direction X of the hull 2 under the above conditions, the horizontal section Sh (z) The outline Ls (z) having a length of 50% to 100%, preferably 60% to 100% of the length of the outline Ls (z) is in the sector region Rα (z). It is configured so that the position of the virtual point P2 (z) exists. In other words, when the virtual point P2 (z) is provided at an appropriate position on the hull center line Lc, the horizontal cross section Sh (z) is located inside the sector region Rα (z) having the virtual point P2 (z) as a vertex. The outer shape Ls (z) has a length of 50% to 100%, preferably 60% to 100%.

According to this configuration, the stern shape of the structure 20 on the water surface of the upper structure 20 is a relatively wide open V having an angle α on one side of 40 degrees (degrees) to 80 degrees, preferably 55 degrees to 65 degrees. It can be a letter shape. With this stern shape, the flow at the stern is similar to the flow at the rear end of the wing, and lift can be generated in the same direction as the wing when the wind is diagonally headed.

In other words, the upper structure 20 having the stern shape improves air flow at the stern when the wind is diagonally headed, and the flow of the structure 20 on the water surface to the rear becomes smooth. The portion can function as a wing and generate lift. The thrust of the ship 1 can be obtained by the component in the longitudinal direction X of the hull 2 of this lift. The generation of lift and thrust has been confirmed by the results of wind tunnel experiments.

As in the case of the ship 1A of the second embodiment, in the ship having the upper structure 20 at the stern part, the container (loading cargo) 30 is loaded on the upper deck 3 and the timber or the like is loaded on the timber carrier ship. Therefore, the shape on the upper deck 3 is an elongated shape as a whole. In such a ship, the upper structure 20 from the bow to the stern and the loaded cargo 30 have a shape similar to the wing shape, so the stern side shape of the upper structure 20 has substantially the same function as the rear end of the wing. With such a shape, it is possible to increase the lift generated in an oblique wind, and to obtain a thrust from this lift.

Further, according to this configuration, since the wind escape on the stern side of the upper structure 20 is improved with respect to the oblique head wind, the generation of vortex in the stern side portion is reduced, and the hull caused by the wind in this portion is reduced. The wind force in the lateral direction Y can be reduced, and the turning moment due to the wind acting on the upper structure 20 can be reduced. As a result, the rudder angle for canceling the turning moment can be reduced, the propulsion efficiency can be improved from this aspect, and the maneuverability can also be improved. The effect related to the turning moment can be exhibited even when the loaded cargo 30 is not loaded on the upper deck 3 in front of the upper structure 20, and the propulsion efficiency and the maneuverability can be improved.

Also, due to the obtuse stern side shape of the upper structure 20, if the vessels have the same overall length, there is also an advantage that the volume increases and the load capacity increases accordingly.

Further, the side wall portion (wall surface of the upper structure 10) 28 of the stern side first range Rx1 that forms the stern side of the structure 20 on the water surface, in the shape of each horizontal cross section Sh (z) of the upper and lower first range Rz1, A smooth curved portion where the unevenness width is 5% or less of the maximum width Bmax of the upper structure 20, or a straight line portion where the unevenness width is 5% or less of the maximum width Bmax of the upper structure 20, or It is preferable to form a combination of both. By adopting this configuration, it is possible to suppress the occurrence of a large vortex due to separation in the flow at the curved portion or the straight portion.

Further, the side wall 28 forming the stern side of the water surface structure 20 has an inclination angle β of 30 degrees or more and 90 degrees or less with respect to the horizontal plane in the stern side first range Rx1 and the upper and lower first range Rz1. If it forms in this, the eddy current which arises in the corner | angular part of the stern side upper surface 27 and the side wall part 28 which forms the stern side of the water surface structure 20 can be suppressed. The side wall portion 28 is preferably formed in a curved surface shape in which the whole or a part of the upper side of the water surface is convex outward. In this case, the angle formed by the contact surface at each point on the curved surface with the horizontal surface is set. The inclination angle is β.

If the inclination angle β is smaller than 30 degrees, the lower part of the stern side part will extend greatly in the stern direction, and if it is larger than 90 degrees, it becomes impractical. Furthermore, by providing cornering or rounding at the corners of the stern side upper surface 27 and the side wall portion 28, it becomes possible to more effectively suppress vortex flow.

Further, in the cargo ship 1A in which the upper structure 20 is the water surface structure 20, it is preferable that the stern side first range Rx1 and the upper and lower first range Rz1 are further configured as follows.

That is, as shown in FIG. 8, 50% or more of the side wall 28 of the upper structure 20 is formed by a straight line L3 (z) in each horizontal section, and the first line L3 (z) with respect to the hull center line Lc. An average value in the first vertical range Rz1 with respect to the vertical direction Z of the angle α (z) is defined as a first average angle αm. In addition, the straight line L4 represents 20% or more, preferably 30% or more, more preferably 40% or more on the stern side of the front surface of the upper structure 20 in the side wall (dry ridge) 8 of the hull 2 below the upper structure 20. (Z).

At the same time, the average value in the range of the freeboard 8 of the hull 2 with respect to the vertical direction Z of the third angle θ (z) with respect to the hull center line Lc of this straight line L4 (z) is defined as the third average angle θm, and the angle γ2 is set. 5 degrees. At this time, the relationship between the first average angle αm and the third average angle θm is a relationship of (αm−γ2) ≦ θm ≦ (αm + γ2).

As a result, there is no significant difference between the first average angle αm and the third average angle θm in a plan view between the stern-side upper structure 20 and the freeboard 8 of the hull 2. 20 and the hull 2 are less likely to be disturbed by the vertical flow, and a planar flow is easily maintained, so that the wing-shaped rear end effect of the upper structure 20 and the hull 2 can be exhibited. Further, it is possible to improve the propulsion performance due to the generation of lift while suppressing an increase in the wind pressure resistance of the entire ship 1A in an oblique headwind.
The eddy current can be suppressed.

Next, a ship with a low wind pressure resistance (hereinafter referred to as a ship) according to the third embodiment will be described. As shown in FIGS. 9 and 10, the ship 1 </ b> B according to the third embodiment is obtained by further limiting the stern shape in the ship 1 according to the first embodiment. FIG. 9 shows an example of a container ship.

This ship 1B is a container ship or the like, and has an upper structure 20 having a bridge 21 and a residential area 22 on the upper deck 3, but the upper structure 20 is not on the stern side but on the bow side in the longitudinal direction X of the hull. Ships placed at intermediate positions are mainly targeted.

In the ship 1B in which the hull 2 is the water surface structure 2, the stern side first range Rx1 and the upper and lower first range Rz1 are provided in the same manner as the ship 1 of the first embodiment. Rx1 and the upper and lower first range Rz1 are set as the stern specific range Sa1, and the stern shape in this portion is formed as follows.

That is, 30% or more of the stern side of the hull (water surface structure) 2 is formed by a straight line L4 (z), and the vertical direction of the third angle θ (z) of the straight line L4 (z) with respect to the hull center line Lc ( When the average value for Z) is the third average angle θm, the angle γ2 is 20 degrees, preferably 10 degrees, more preferably 5 degrees, and θ1 is 50 degrees, the third average angle θm is (θ1 −γ2) ≦ θm ≦ (θ1 + γ2).

According to this configuration, even in a ship 1B in which an upper structure 20 such as a container ship is arranged forward or in the middle of the hull longitudinal direction Z, the stern shape of the hull 2 exhibits the wing-shaped rear end effect. The propulsion performance resulting from the generation of lift can be improved while suppressing an increase in wind pressure resistance of the entire ship in an oblique headwind.

Further, depending on the manner in which the loaded cargo 30 such as a container is arranged on the upper deck 3, the shape of the cargo at the time of loading is matched to the stern shape of the hull 2 or is made similar to that of the hull 2. In addition to the wing shape rear end effect on the stern side, the wing shape rear end effect can be exhibited also in the overall shape of the cargo 30 loaded on the upper deck 3.

According to the

vessels

1, 1A, 1B having the above-described configuration, the wind pressure area on the surface of the water is relatively large, and the influence of the diagonally headed wind is reduced in an automobile carrier ship, a passenger ship, a container ship, a timber carrier ship, etc. At the same time, lift is generated by the

surface components

2 and 20 formed by the hull 2 or the upper structure 20 and the loaded cargo 30 such as a container, and thrust can be obtained from the components in the longitudinal direction X of the hull 2 of this lift. Thus, the propulsion performance of the

ships

1, 1A, 1B can be improved. As a result, fuel consumption can be improved and energy saving can be achieved.

1, 1A, 1B Ship 2 Hull (water structure)
3 Upper deck 8 Side 20 Upper structure 21 Bridge 22 Residence area 30 Cargo (container)
A. P. Stern perpendicular Bmax Maximum width F. P. Bow vertical line L1 First inclined line L2 Second inclined line Lc Hull center line Lpp Vertical length Ls (z) Horizontal cross section outline P1 First position P2 Virtual point Pa Hull tail tail Rx1 Stern side first range Rz1 Up and down first 1 range Rα (z) Fan-shaped region Sa1 Stern specific range Sh (z) Horizontal cross section X in stern specific range Y Front / rear direction Y Hull's left / right direction Z Hull's vertical direction α Side angle α1 First angle α2 Second angle β Inclination angle θ Third angle

Claims

In a ship with a voyage speed of 0.13 to 0.30 in terms of fluid number, at least one of the hull on the surface of the water or the upper structure provided on the upper deck,
A point on the hull centerline at the rearmost portion of the maximum width of the above-ground structure on the stern side is defined as a first position, and a stern-side first range is defined between the first position and the last tail of the hull. A range of 50% or more and 100% or less in an arbitrary continuous portion in the vertical direction of
In each horizontal cross section parallel to the water surface in the first range on the stern side of the structure on the water surface and the first range above and below,
A line extending from a virtual point on the hull center line at a first angle with respect to the bow direction in the front-rear direction of the hull is defined as a first inclined line, and a line extending from the virtual point at a second angle with respect to the bow direction in the front-rear direction of the hull. Is the second inclined line, the first angle is 50 degrees, the second angle is 80 degrees, the fan-shaped region is between the first inclined line and the second inclined line, and the virtual point is the center of the hull. When moving on the line and moving the sector area in the longitudinal direction of the hull,
A ship with low wind pressure resistance, characterized in that the position of the imaginary point is such that an outline having a length of 50% or more and 100% or less of the length of the outline of the horizontal section falls within the fan-shaped region.
In the shape of each horizontal section of the upper and lower first range, the side wall portion of the first range on the stern side has a smooth curved portion in which the width of the unevenness is 5% or less of the maximum width of the structure on the water surface, Or the ship with little wind pressure resistance of Claim 1 formed in the linear part from which the width | variety of an unevenness | corrugation becomes 5% or less of the maximum width of the said structure on a water surface, or the combination of both.
The side wall portion that forms the stern side of the structure on the water surface is formed so as to have an inclination angle of 30 degrees or more and 90 degrees or less with respect to the horizontal plane in the first range on the stern side and the first range in the upper and lower sides. The ship with little wind pressure resistance according to claim 1 or 2.
In the case where the upper structure is a water surface structure,
In the first range on the stern side and the first range on the upper and lower sides,
In each horizontal section, 50% or more of the side wall portion of the superstructure is formed with a straight line, and the average value in the first vertical range with respect to the vertical direction of the first angle with respect to the center line of the hull is the first average angle αm. age,
20% or more of the stern side of the side wall of the hull under the superstructure is formed in a straight line with respect to the front side of the superstructure, and the hull in the vertical direction of the third angle with respect to the straight hull centerline. When the average value in the range of dry ridge is the third average angle θm and the angle γ1 is 5 degrees,
2. The ship with low wind pressure resistance according to claim 1, wherein the relationship between the first average angle αm and the third average angle θm is a relationship of (αm−γ1) ≦ θm ≦ (αm + γ1).
In the case where the hull is a water surface structure,
In the first range on the stern side and the first range on the upper and lower sides,
30% or more of the stern side of the structure on the water surface is formed as a straight line, the average value of the third angle with respect to the center line of the hull in the vertical direction is the third average angle θm, the angle γ2 is 20 degrees, When θ1 is 50 degrees,
2. The ship with low wind pressure resistance according to claim 1, wherein the third average angle θm has a relationship of (θ1−γ2) ≦ θm ≦ (θ1 + γ2).