CN113799914B

CN113799914B - Stern structure and ship

Info

Publication number: CN113799914B
Application number: CN202111275005.1A
Authority: CN
Inventors: 田中文; 何珍; 伍蓉晖; 王开贵; 易歆; 彭翔
Original assignee: Guangzhou Wenchong Shipyard Co Ltd
Current assignee: Guangzhou Wenchong Shipyard Co Ltd
Priority date: 2021-10-29
Filing date: 2021-10-29
Publication date: 2023-01-06
Anticipated expiration: 2041-10-29
Also published as: CN113799914A

Abstract

The invention belongs to the technical field of ships, and particularly discloses a stern structure of a ship and the ship. The stern structure comprises a hull stern part and a propeller, the diameter of the propeller is D, the hull stern part is integrally of a square stern part structure, the bottom of the hull stern part is provided with an inwards concave fornix part, and the fornix part is positioned above the propeller; two end points of the dome part are respectively a point a and a point b, two intersection points of a contour line of the propeller and a characteristic height line are respectively a point e and a point s, the point a, the point s, the point e and the point b are sequentially arranged along a stern to the bow, the horizontal distance between the point a and the point s is La, the horizontal distance between the point b and the point e is Lb, the minimum distance between the highest point of the propeller and the dome part is Lmin, la = (0.12-0.35) D, lb is more than or equal to 0.2D, lmin = (0.14-0.35) D, and preferably 0.3D. The ship comprises the stern structure. The stern structure and the ship disclosed by the invention can better realize the combination of the square stern and the large-diameter propeller, reduce the resistance and improve the propulsion efficiency.

Description

Stern structure and ship

Technical Field

The invention relates to the technical field of ships, in particular to a stern structure and a ship.

Background

At present, the specific gravity of fuel oil cost is about 30% -40% in the operating cost of ocean-going ships, and how to reduce energy consumption is an important problem in ship design.

In the existing ship design, two ways are generally adopted to realize the reduction of energy consumption: the first mode is to develop an energy-saving ship profile, and the resistance of the ship during navigation is reduced through the ship profile arrangement, so that the power of the ship during navigation is saved; the second approach is to develop a long-stroke, low-speed main engine that requires relatively little profile for the vessel but works with a larger diameter propeller.

The existing ship mainly adopts a square stern part, the gradient of a longitudinal line of the stern part is gradually close to a straight line, water flow can flow along the longitudinal line approximately, and the torsion and bending degree of high-speed water flow is reduced, so that the energy loss can be reduced, and the resistance performance is improved. However, when the diameter of the propeller is large, the distance between the tip end of the blade of the propeller and the outer wall of the ship body is likely to be small, and the problems of increased cavitation and enhanced excitation in the operation process of the propeller are caused, so that the propulsion performance of the propeller is affected, and the energy-saving advantage of the large-diameter propeller is difficult to exert.

Disclosure of Invention

The invention aims to provide a stern structure to improve the applicability of a large-diameter propeller on a square stern, reduce resistance and save energy consumption.

Another object of the present invention is to provide a ship, which can improve the propulsion efficiency of the ship, reduce the resistance of the ship during sailing, and save the energy consumption of the ship during sailing.

In order to realize the purpose, the invention adopts the following technical scheme:

a stern structure comprises a hull stern part and a propeller arranged on the hull stern part, wherein the diameter of the propeller is D, the whole hull stern part is of a square stern part structure, the bottom of the hull stern part is provided with an inwards concave fornix part, and the fornix part is positioned above the propeller;

on a longitudinal plane of a ship, two end points of the dome portion are respectively a point a and a point b, two intersection points of a contour line of the propeller and a characteristic height line are respectively a point e and a point s, the point a, the point s, the point e and the point b are sequentially arranged from a stern to a bow, the horizontal distance between the point a and the point s is La, the horizontal distance between the point b and the point e is Lb, the minimum distance between the highest point of the propeller and the dome portion is Lmin, la = (0.12-0.35) D, lb is larger than or equal to 0.2D, lmin = (0.14-0.35) D, and the height of the characteristic height line from a mounting center of the propeller is 0.35D.

As an optional technical scheme of a stern structure, lb is less than or equal to 0.4D.

As an optional technical scheme of the stern structure, on a ship transverse section passing through the point a, a distance between a transverse end point of the vault and a middle longitudinal plane of the ship is CLa, and CLa = (0.12-0.20) D;

and/or on a ship cross section passing through the point b, the distance between the transverse end point of the vault part and the middle longitudinal plane of the ship is CLb, and the CLb = (0.30-0.40) D.

As an optional technical solution of the stern structure, on the middle longitudinal plane of the ship, the dome portion has a point c, the point c is located between the point a and the point b, and a distance between a highest point of the propeller and the point c is the Lmin;

and on the ship transverse section passing through the point c, the distance between the transverse end point of the vault part and the middle longitudinal plane of the ship is CLc, and the CLc = (0.20-0.30) D.

As an optional technical scheme of a stern structure, a dome longitudinal profile formed on the middle longitudinal plane of the ship by the dome part is a smooth curve, and the slope of the dome longitudinal profile is gradually reduced from the point a to the point b.

As an optional technical scheme of a stern structure, the longitudinal line of the dome is horizontally arranged on the tangent line of the point a;

and/or the slope of the tangent of the dome longitudinal section line at the point b is less than or equal to-1.

As an optional technical scheme of a stern structure, the vault part is in smooth transition connection with a stern main body of the stern part of the ship body.

As an optional technical scheme of the stern structure, the width of the stern of the ship body between the 0 station position and the 1 station position is equal.

As an optional technical scheme of a stern structure, the hull stern has the installation the tailshaft of screw, the tailshaft is located the below of vault portion, the rearmost end of tailshaft is located a point with between the b point, just the upper end of tailshaft with the lower extreme smooth connection of vault portion, the lower extreme light of tailshaft extends to the bottom of hull stern portion.

A ship comprising an aft structure as described above.

The invention has the beneficial effects that:

according to the stern structure provided by the invention, as the whole stern part of the ship body is of a square structure, the problem of large load capacity of the ship can be solved under the condition that the ship has enough water displacement; the bottom through at square hull stern sets up the vault portion for the vault portion can provide more spaces for the installation of screw, and through the parameter setting to La, lb and Lmin, increase the clearance between screw and the hull stern portion, thereby reduce the cavitation quantity when the screw moves, reduce pulsating pressure, improve the wake flow condition, can be under the circumstances of non-resistance, improve the suitability of major diameter screw on square stern, when improving the resistance characteristic of boats and ships when navigating, increase propulsion efficiency, and then effectively energy saving consumes.

According to the ship provided by the invention, by adopting the stern structure, the propelling efficiency of the ship can be improved, the resistance of the ship during navigation is reduced, and the energy consumption is saved.

Drawings

Fig. 1 is a cross sectional line drawing of a stern structure of a ship according to an embodiment of the present invention;

fig. 2 is a longitudinal section line drawing of a stern structure of a ship in a longitudinal section of the ship according to an embodiment of the present invention;

fig. 3 is a cross sectional line drawing of a stern structure of a ship according to an embodiment of the present invention in a partial cross section.

The figures are labeled as follows:

1. a hull stern; 11. a dome portion; 12. a stern body; 13. a tail shaft; 2. a propeller.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. It should be further noted that, for the convenience of description, only some structures related to the present invention are shown in the drawings, not all of them.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless expressly stated or limited otherwise, the recitation of a first feature "on" or "under" a second feature may include the recitation of the first and second features being in direct contact, and may also include the recitation that the first and second features are not in direct contact, but are in contact via another feature between them. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used in an orientation or positional relationship based on that shown in the drawings only for convenience of description and simplicity of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to be limiting.

As shown in fig. 1 and fig. 2, the present embodiment provides a stern structure, which can be applied to a low-and-medium-speed ship to reduce the resistance of the ship during navigation, improve the adaptability between the stern profile and the large-diameter propeller, and save the energy consumption of the ship.

Specifically, the stern structure provided by this embodiment is mainly suitable for ships with friedel numbers Fr = 0.18-0.26 and square coefficients CB = 0.57-0.68, and is particularly suitable for container ships under the design parameters.

In order to introduce ship parameters conveniently, the design navigational speed of the ship is defined as Vs, the length between fore and aft vertical lines is defined as Lpp, and the width of the ship is defined as B. In the process of designing the ship, the ship is equally divided into 20 stations from the stern to the bow along the ship length direction, wherein the position corresponding to the vertical line of the stern post is the 0 th station, the position corresponding to the vertical line of the bow post is the 20 th station, and the length represented by each complete station is 0.05Lpp.

In this embodiment, the stern line between 0 station and 1 station is mainly modified, so station labels are added between 0 station and 1 station every 0.25 station. In this embodiment, the stern structural portion protrudes from the vertical line of the stern post in the direction away from the bow, that is, on the ship transverse sectional line diagram, there is a stern tail end station position with a station position identifier smaller than 0, and the labeled position of the stern tail end station position is the tail end position of the stern in the ship length direction. In this embodiment, the stern end station is identified as-0.325 station, i.e., representing that the stern end is 0.325Lpp/20 from the vertical line of the stern post. It is understood that in other embodiments, the stern end station number may be set as desired.

Fig. 1 shows a cross sectional view of a ship between a stern end station and a stern 1 station, and at each station, the ship stern structure includes a ship stern 1 and a propeller 2 disposed at the ship stern 1, as can be seen from fig. 1. The hull stern part 1 is a square stern part on the whole, namely the width of the ship is approximately the same between the stern tail end station position and the station position 1, and the bottom molded line of the hull stern part 1 is in smooth and slow transition on two sides in the ship length direction. The height of the bottom of the stern at the middle longitudinal surface of the ship is gradually reduced along the direction towards the ship bow, a tail shaft 13 is arranged between a 0.5 station and a 1 station of the stern part 1 of the ship body, the tail shaft 13 is lower than the designed waterline position of the ship, and a propeller 2 is arranged on the tail shaft 13.

As shown in fig. 1 and 2, the stern portion 1 of the hull is provided with a dome portion 11 recessed toward the bow in the middle in the width direction, and the dome portion 11 is located above the propeller 2. On the middle longitudinal plane of the ship, two end points of the dome part 11 are respectively a point a and a point b, two intersection points of a contour line of the propeller 2 and a characteristic height line are respectively a point e and a point s, the point a, the point s, the point e and the point b are sequentially arranged from the stern to the bow, the horizontal distance between the point a and the point s is La, the horizontal distance between the point b and the point e is Lb, the minimum distance between the highest point of the propeller 2 and the dome part 11 is Lmin, la = (0.12-0.35) D, lb is more than or equal to 0.2D, lmin = (0.14-0.35) D, and the height of the characteristic height line from the installation center of the propeller 2 is 0.35D.

According to the stern structure of the ship provided by the embodiment, the stern part 1 of the ship body is integrally of a square structure, so that the problem of large load capacity of the ship can be solved under the condition that the ship has enough water displacement; set up vault portion 11 through the bottom at square hull stern portion 1 for vault portion 11 can provide more spaces for the installation of screw 2, and through the parameter setting to La, lb and Lmin, increase the clearance between screw 2 and the hull stern portion 1, thereby reduce the vacuole quantity when screw 2 moves, reduce pulsating pressure, improve the wake flow condition, can be under the condition of not obviously increasing the resistance, improve the suitability of major diameter screw 2 on square stern, when improving the resistance characteristic when boats and ships navigate, increase propulsive efficiency, and then effectively save the energy consumption.

It should be noted that, in the present invention, the fore-and-aft direction is referred to as the ship length direction, and the fore is referred to as the fore, and the aft is referred to as the aft, that is, the front end of a certain structure refers to the end facing the fore, and the rear end or the aft is the direction facing the aft.

In the present embodiment, the widths of the hull stern portions 1 from the 0-station position to the 1-station position are equal, and preferably, the widths of the hull stern portions 1 after the 1-station position are equal. However, it is understood that the beam width of the stern of the hull at the rear side of the 1 st station may gradually decrease along the direction from the 1 st station to the 0 st station, and may be approximately regarded as a square stern structure when the beam width decreases from the 1 st station to the 0 st station in a smaller range.

Further, in the present embodiment, lmin is preferably 0.3D, and Lb is preferably less than or equal to 0.4D.

In the present embodiment, the dome 11 is an inward concave smooth curved surface structure, and preferably, the dome 11 is in smooth transition connection with the stern main body 12, so as to prevent the water flow from generating a large turbulent flow at the junction of the dome 11 and the stern main body 12, reduce the resistance of the ship during navigation, prevent the water flow from separating, and avoid the reduction of the water amount entering the propeller 2, thereby reducing cavitation and excitation when the propeller 2 operates.

The longitudinal dome line formed on the longitudinal plane of the ship by the dome part 11 is a smooth curve, the tangent slope of the longitudinal dome line is less than or equal to 0, and the tangent slope gradually decreases from a point a to a point b, so that smooth transition from the point a to the point b can be realized, meanwhile, smooth transition connection between the dome part 11 and the stern main body 12 at the rear end is facilitated, smooth transition connection between the front end of the dome part 11 and the tail shaft 13 is facilitated, and resistance is further reduced.

In this embodiment, in the longitudinal section of the ship, the profile of the stern body 12 at the rear end of the dome portion 11 is an inclined straight line segment extending obliquely downward from back to front, and the inclination angle of the inclined straight line segment relative to the horizontal plane is less than 45 °. Preferably, the longitudinal line of the dome is horizontally arranged at the tangent line of the point a, which is more favorable for reducing the water flow separation when the water flow passes through the dome part 11, and is easier for the transition connection of the rear end of the stern main body 12 which is inclined backwards and extends upwards.

Further, the slope of the tangent to the dome longitudinal section line at point b is less than or equal to-1, thereby enabling better transitional coupling with the structure located below the dome portion 11.

In the embodiment, the tail shaft 13 is located below the dome portion 11, the tail shaft 13 is of a structure with a narrow rear end and a wide front end, the upper side of the tail shaft 13 extends forwards and upwards in an inclined mode to be connected with the lower end of the dome portion 11, and the lower side of the tail shaft 13 extends downwards and forwards in an inclined mode to be connected with the bottom of the ship. On the middle longitudinal plane of the ship, the rearmost end of the tail shaft 13 is located between the points a and b, a C-shaped space with a backward opening is formed by the upper side of the tail shaft 13 and the fornix part 11 in an enclosing mode, and the upper end of the propeller 2 extends into the C-shaped space.

It will be appreciated that as the diameter of the propeller 2 increases, the height of the rear end of the tail shaft 13 also needs to be raised so that the height difference between the lowest point of the ground propeller 2 and the hull base line is at least greater than 50mm, i.e. the structure of the tail shaft 13 is adapted to the size and dimensions of the propeller 2 during the actual design of the ship. The structural design principle of the tail shaft 13 can refer to the prior art, and is not described in detail here.

Preferably, the foremost end of the upper side of the C-shaped space is an f point, the f point is located at the front side of the b, the f point is located on the tail shaft 13, and a tangent line of a longitudinal section line of the tail shaft 13 at the f point is vertically arranged, so that the smoothness of connection is further improved, and the appearance attractiveness of the stern structure and the ship is improved.

In the present embodiment, the dome portion 11 is disposed between the 0-station position and the 0.75-station position, and the propeller 2 is disposed between the 0.25-station position and the 0.5-station position.

On the middle longitudinal plane of the ship, the vault part 11 has a point c, the point c is positioned between the point a and the point b, and the distance between the highest point of the propeller 2 and the point c is Lmin.

As shown in fig. 3, the cross sectional line of the stern portion 1 of the hull isbase:Sub>A plurality of semi-cross sectional line diagrams, wherein the line designated bybase:Sub>A-base:Sub>A is the cross sectional line diagram of the stern portion 1 of the hull passing throughbase:Sub>A pointbase:Sub>A, the line designated by B-B is the cross sectional line diagram of the stern portion 1 of the hull passing throughbase:Sub>A point B, and the line designated by C-C is the cross sectional line diagram of the stern portion 1 of the hull passing throughbase:Sub>A point C. As shown in fig. 3, the distance between the transverse end of the dome portion 11 on the cross section passing through the point a and the middle longitudinal plane of the ship is CLa, CLa = (0.12 to 0.20) D; the distance between the transverse end point of the vault part 11 on the cross section passing through the point b and the middle longitudinal plane of the ship is CLb, and CLb = (0.3-0.40) D; the distance between the transverse end point of the dome portion 11 on the cross section passing through the point c and the middle longitudinal plane of the ship is CLc, CLc = (0.20 to 0.30) D. Cla, CLb and CLc can further reduce the generation of wake flow and cavitation, reduce the resistance of the ship during navigation and optimize the line structure of the stern part 1 of the ship body.

On the semi-section line graph, the molded line of the fornix part 11 is in smooth transition connection with the molded line of the stern main body 12, so that the water flow is prevented from generating large disorder at the junction of the fornix part 11 and the stern main body 12, and the resistance is reduced; in addition, the water flow separation is prevented, the water amount flowing into the propeller area is reduced, and cavitation and vibration excitation are avoided.

The embodiment also provides a ship comprising the stern structure. The ship provided by the embodiment can improve the propelling efficiency of the ship, reduce the resistance of the ship during navigation and save energy consumption by adopting the stern structure.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the particular embodiments described herein, and that various obvious changes, rearrangements and substitutions will now be apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. The stern structure is characterized by comprising a hull stern part (1) and a propeller (2) arranged on the hull stern part (1), wherein the diameter of the propeller (2) is D, the hull stern part (1) is integrally of a square stern structure, the bottom of the hull stern part (1) is provided with an inwards concave fornix part (11), and the fornix part (11) is positioned above the propeller (2);

on a longitudinal plane of a ship, two end points of a vault part (11) are respectively a point a and a point b, two intersection points of a contour line of a propeller (2) and a characteristic height line are respectively a point e and a point s, the point a, the point s, the point e and the point b are sequentially arranged from a stern to a bow, the horizontal distance between the point a and the point s is La, the horizontal distance between the point b and the point e is Lb, the minimum distance between the highest point of the propeller (2) and the vault part (11) is Lmin, la = (0.12 to 0.35) D, lb is not less than 0.2D, lmin = (0.14 to 0.35) D, and the height of the characteristic height line from a mounting center of the propeller (2) is 0.35D;

the vault part (11) is provided with a point c, the point c is positioned between the point a and the point b, and the distance between the highest point of the propeller (2) and the point c is Lmin;

on the cross section of the ship passing through the point c, the distance between the transverse end point of the vault (11) and the middle longitudinal surface of the ship is CLc, and the CLc is (0.20 to 0.30) D.

2. The stern structure according to claim 1 wherein Lb is ≦ 0.4D.

3. The stern structure according to claim 1, wherein, on a ship cross section passing through the point a, the distance between the transverse end point of the vault (11) and the longitudinal plane of the ship is CLa, and the CLa = (0.12 to 0.20) D;

and/or on the cross section of the ship passing through the point b, the distance between the transverse end point of the vault part (11) and the middle longitudinal plane of the ship is CLb, and the CLb = (0.30 to 0.40) D.

4. The stern structure according to claim 1, wherein the dome longitudinal section line of the dome portion (11) formed on the longitudinal plane of the ship is a smooth curve, and the tangential slope of the dome longitudinal section line is less than or equal to 0 and gradually decreases from the point a to the point b.

5. The stern structure of claim 4 wherein the vault longeron is disposed horizontally tangent to the point a;

and/or the slope of the tangent line of the dome longitudinal section line at the point b is less than or equal to-1.

6. The stern structure according to any of claims 1 to 5 wherein the dome (11) is in smooth transition with the stern body (12) of the hull stern (1).

7. The stern construction according to any of claims 1-5, characterised in that the width of the hull stern (1) is equal between 0 and 1 standing.

8. The stern structure according to any one of claims 1 to 5 wherein the hull stern (1) has a stern shaft (13) to which the propeller (2) is mounted, the stern shaft (13) being located below the dome (11), the rearmost end of the stern shaft (13) being located between the points a and b, and the upper end of the stern shaft (13) being in smooth connection with the lower end of the dome (11), the lower end of the stern shaft (13) extending smoothly to the bottom of the hull stern (1).

9. A ship comprising an aft structure according to any one of claims 1-8.