Bow thruster mounting device and its design method, bow thruster system

Abstract

This invention belongs to the field of marine technology and discloses a bow thruster installation device and its design method, as well as a bow thruster system. The bow thruster installation device is used to install the propeller of the bow thruster system and includes an installation cylinder. The installation cylinder is disposed through the hull along a predetermined direction, and the installation cylinder has an inlet edge extending to the outer surface of one side of the hull. The inlet edge is provided with a first arc-shaped chamfer, which is used to guide fluid into the installation cylinder. This invention ensures the propulsion efficiency of the bow thruster system. Because the fluid does not separate from the inner wall of the installation cylinder, the flow field is more uniform. Non-uniform flow field is a major source of vibration and noise. This invention also reduces harmful vibration and noise, ensuring the normal operation of shipboard equipment and personnel, as well as personnel comfort.

Description

Technical Field

[0001] This invention relates to the field of cruise ship technology, and in particular to a bow thruster installation device and its design method, and a bow thruster system. Background Technology

[0002] A bow thruster, or bow thruster system, is installed at the bow of a ship to improve its maneuverability. Specifically, during the berthing of a cruise ship at a port, multiple bow thrusters are used to ensure efficient and accurate berthing at the mooring point. These systems generate lateral thrust by rotating clockwise or counterclockwise, and through speed control, gradually adjust the cruise ship's berthing attitude to achieve a precise, predetermined berthing position. Typically, a bow thruster system includes a motor and a propeller. The motor controls the propeller's clockwise or counterclockwise rotation, enabling lateral movement of the ship.

[0003] In existing technologies, the bow thruster system is installed in a mounting cylinder, which is connected to the hull. The edges of the mounting cylinder in existing technologies have flat cross-sections. However, because the edges of the mounting cylinder have sharp angles relative to the outer surface of the hull, the fluid flow through this location is uneven, resulting in significant vibration and noise. The bow thruster area of ​​large cruise ships often houses vibration-sensitive cabins such as living quarters, restaurants, conference rooms, and the bridge. To avoid harmful vibrations and noise, ensure the normal operation of shipboard equipment and personnel, and maintain passenger comfort, the design of the bow thruster should not only meet various technological requirements but also consider vibration and noise reduction requirements. Summary of the Invention

[0004] The purpose of this invention is to provide a bow thruster installation device and its design method, as well as a bow thruster system, to solve the problems of excessive vibration and noise in the prior art.

[0005] Based on the above concept, the technical solution adopted by this invention is as follows:

[0006] A bow thruster mounting device for mounting the propeller of a bow thruster system includes a mounting cylinder that extends through the hull in a predetermined direction and has an inlet edge extending to the outer surface of one side of the hull. The inlet edge is provided with a first arc-shaped chamfer for guiding fluid into the mounting cylinder.

[0007] Preferably, the hull is provided with mounting holes, the mounting cylinder is installed in the mounting holes, the first port of the mounting cylinder is located on the first surface of the hull, and the surface where the first port is located is coplanar with the first surface; the second port of the mounting cylinder is located on the second surface of the hull, and the surface where the second port is located is coplanar with the second surface.

[0008] Alternatively, a portion of the hull may form the mounting cylinder.

[0009] Preferably, the transverse contour line of the first arc-shaped chamfer is the first contour line, and the radius of the circle containing the first contour line is 250mm to 350mm.

[0010] Preferably, the transverse contour line of the first arc-shaped chamfer is the first contour line, the first contour line is arc-shaped, and the tangent of the first contour line near the inner wall end of the mounting cylinder is parallel to the axis of the mounting cylinder.

[0011] The transverse cross-sectional profile of one side surface of the hull is an arc-shaped second profile line. The second profile line is connected to the first profile line, and the tangent line of the second profile line near one end of the first profile line is the first tangent line, and the tangent line of the first profile line near one end of the second profile line is the second tangent line. The first tangent line and the second tangent line coincide.

[0012] Preferably, the mounting cylinder has an outlet edge extending to the other side surface of the hull, and the outlet edge is provided with a second arc-shaped chamfer for guiding fluid out of the mounting cylinder.

[0013] Preferably, the transverse contour line of the second arc-shaped chamfer is the third contour line, the third contour line is arc-shaped, and the tangent line of the third contour line near the inner wall end of the mounting cylinder is parallel to the axis of the mounting cylinder.

[0014] The transverse cross-sectional profile of the other side surface of the hull is an arc-shaped fourth profile line. The fourth profile line is connected to the third profile line, and the tangent line of the fourth profile line near one end of the third profile line is the third tangent line. The tangent line of the third profile line near one end of the fourth profile line is the fourth tangent line. The third tangent line and the fourth tangent line coincide.

[0015] Preferably, the bow thruster mounting device further includes a first guide member, which is streamlined and disposed on the inner wall of the mounting cylinder, with one end extending to the inlet edge.

[0016] The mounting cylinder has an outlet edge extending to the other side surface of the hull, and the bow thruster mounting device further includes a second guide member, which is streamlined and disposed on the inner wall of the mounting cylinder, with one end extending to the outlet edge.

[0017] A design method for a bow thruster mounting device, used to design the bow thruster mounting device as described above, the design method for the bow thruster mounting device includes the following steps:

[0018] An installation cylinder is formed on the hull, the installation cylinder is disposed through the hull in a predetermined direction, and the installation cylinder has an opening extending to the outer surface of one side of the hull;

[0019] The opening is chamfered to form an inlet edge with a first arc-shaped chamfer.

[0020] A bow thruster system, including the bow thruster mounting device as described above, or including a bow thruster mounting device designed according to the design method of the bow thruster mounting device described above;

[0021] The bow thruster system also includes a power unit and a propeller. The power unit is installed in the bow thruster mounting device and is used to drive the propeller to rotate. The propeller is disposed in the mounting cylinder.

[0022] Preferably, at least a portion of the power device is disposed within the mounting cylinder, and the corners of the portion of the power device located within the cylinder are provided with rounded chamfers.

[0023] The beneficial effects of this invention are:

[0024] The bow thruster installation device and its design method, as well as the bow thruster system provided by this invention, have an inlet edge extending to the outer surface of one side of the hull, and the inlet edge is provided with a first arc-shaped chamfer. This first arc-shaped chamfer is used to guide the fluid into the installation cylinder. The design of the inlet edge without protruding edges optimizes the inlet edge, thereby reducing the separation of the fluid from the inner wall of the installation cylinder under the action of the inlet edge, ensuring the propulsion efficiency of the bow thruster system. Since the fluid does not separate from the inner wall of the installation cylinder, the flow field is more uniform. The non-uniformity of the flow field is the main source of vibration and noise. Therefore, this embodiment also reduces harmful vibration and noise, ensuring the normal operation of shipboard equipment and personnel, as well as personnel comfort. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of part of the hull and bow thruster mounting device provided in an embodiment of the present invention. Figure 1 ;

[0027] Figure 2 This is a schematic diagram of the structure of the first arc-shaped chamfer at the inlet edge provided in an embodiment of the present invention;

[0028] Figure 3 This is a partial structural schematic diagram of the bow thruster system provided in an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the structure of part of the hull and bow thruster mounting device provided in an embodiment of the present invention. Figure 2 ;

[0030] Figure 5 This is a schematic diagram of the structure of part of the hull and bow thruster mounting device provided in an embodiment of the present invention. Figure 3 ;

[0031] Figure 6 This is a partial structural schematic diagram of the bow thruster system in the prior art provided by the present invention;

[0032] Figure 7 This is a schematic diagram of the edge of the mounting cylinder in the prior art provided by the present invention;

[0033] Figure 8 This is a flow field diagram of the fluid inside and around the mounting cylinder in the prior art provided by the present invention.

[0034] In the picture:

[0035] 1. Install the cylinder; 11. Inlet edge; 12. First arc chamfer; 121. First outline; 13. Outlet edge; 14. Second arc chamfer; 141. Third outline;

[0036] 10. Hull; 101. Second outline; 102. Fourth outline; L1. First tangent; L2. Third tangent; 20. Cross-section; 30. Vortex region;

[0037] 100. Power equipment; 200. Propeller. Detailed Implementation

[0038] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention. Furthermore, it should be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, not all of them.

[0039] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0040] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature. In the description of this embodiment, unless otherwise specified, "multiple" specifically refers to two or more.

[0042] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0043] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on the other component or it can be located in between the component.

[0044] In existing technologies, such as Figures 6 to 8 As shown, the edge of the mounting cylinder has a planar cross-section 20, resulting in an angle between the edge of the mounting cylinder and the outer surface of the hull 10. When the fluid passes through the angle, under the action of the angle, simulation results from the original design show that there is a large amount of flow separation at the bottom of the middle section of the thrust hole. This separation may affect the torque fluctuation of the propeller 200, leading to an uneven flow field and causing issues such as... Figure 8 The vortex region 30 shown has vortices, which in turn generate a large amount of vibration and noise. Therefore, it is necessary to reduce flow separation and thus reduce propeller torque fluctuation by improving the shape of the side thrust inlet.

[0045] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0046] First, as Figures 1 to 4 As shown, this embodiment provides a bow thruster mounting device for mounting the propeller 200 of the bow thruster system, which can reduce vibration and noise, thereby ensuring the normal operation of shipboard equipment and personnel, as well as personnel comfort.

[0047] like Figure 1 As shown, the bow thruster mounting device includes a mounting cylinder 1. The mounting cylinder 1 extends through the hull 10 along a predetermined direction. In some optional embodiments, the predetermined direction is... Figure 1 The left-right direction shown can also refer to the left-right direction of the hull 10. Furthermore, the mounting cylinder 1 has an inlet edge 11 extending to the outer surface of one side of the hull 10. In this embodiment, the inlet edge 11 is annular, and the inlet edge 11 is provided with a first arc-shaped chamfer 12, that is, the corner of the inlet edge 11 is a rounded chamfer. This first arc-shaped chamfer 12 is used to guide fluid into the mounting cylinder 1, and the fluid contacts the first arc-shaped chamfer 12 when it passes through it.

[0048] The bow thruster mounting device provided in this embodiment has an inlet edge 11 extending to the outer surface of one side of the hull 10, and the inlet edge 11 is provided with a first arc-shaped chamfer 12. The first arc-shaped chamfer 12 is used to guide the fluid into the mounting cylinder 1. The inlet edge 11 has no protruding ridges, which optimizes the inlet edge 11 and reduces the separation of the fluid from the inner wall of the mounting cylinder 1 under the action of the inlet edge 11, thus ensuring the propulsion efficiency of the bow thruster system. Since the fluid does not separate from the inner wall of the mounting cylinder 1, the flow field is more uniform. The non-uniformity of the flow field is the main source of vibration and noise. Therefore, this embodiment also reduces harmful vibration and noise, ensuring the normal operation of shipboard equipment and personnel, as well as personnel comfort.

[0049] In some optional embodiments, the hull 10 is provided with mounting holes, and the mounting cylinder 1 is installed in the mounting holes. That is, the hull 10 and the mounting cylinder 1 are two independent structures. The mounting cylinder 1 can be installed in the mounting holes of the hull 10 through multiple transport and turning plates. In this embodiment, the inlet edge 11 is set on the mounting cylinder 1, which avoids modification of the structure of the hull 10 and the modification is small.

[0050] In this embodiment, the first port of the mounting cylinder 1 is located on the first surface of the hull 10, and the surface where the first port is located is coplanar with the first surface. The second port of the mounting cylinder 1 is located on the second surface of the hull 10, and the surface where the second port is located is coplanar with the second surface. This ensures that the mounting cylinder 1 does not affect the shape of the hull 10, thereby ensuring that the resistance of the hull 10 does not increase. It also facilitates the replacement of the mounting cylinder 1, and has high flexibility and reliability.

[0051] It is understandable that the hull 10 and the mounting cylinder 1 can also be an integral structure. For example, a part of the hull 10 forms the mounting cylinder 1, which improves the integration of the hull 10 and the mounting cylinder 1.

[0052] For example, the lateral contour line of the first arc-shaped chamfer 12 is the first contour line 121, and the radius of the circle containing the first contour line 121 is 250mm to 350mm. For example, the radius of the circle containing the first contour line 121 is 250mm, 280mm, 300mm, 350mm, etc., so that the setting of the first arc-shaped chamfer 12 is neither too large nor too small, thereby ensuring the guiding effect on the fluid and facilitating manufacturing.

[0053] Optionally, such as Figure 4 As shown, the transverse contour line of the first arc-shaped chamfer 12 is the first contour line 121. The first contour line 121 is arc-shaped, and the tangent of the first contour line 121 near the end point of the inner wall of the mounting cylinder 1 is parallel to the axis of the mounting cylinder 1. That is, the inner wall of the mounting cylinder 1 is the tangent surface 20 of the first contour line 121. By making the tangent of the first contour line 121 near the end point of the inner wall of the mounting cylinder 1 parallel to the axis of the mounting cylinder 1, the first arc-shaped chamfer 12 and the inner wall of the mounting cylinder 1 can transition smoothly, thereby preventing the appearance of protruding edges at the connection between the first arc-shaped chamfer 12 and the inner wall of the mounting cylinder 1, which would affect the fluid flow field. This further reduces the generation of vibration and noise, ensuring the propulsion efficiency of the bow thruster system. In this embodiment, the longitudinal contour line of the first arc-shaped chamfer 12 is a ring.

[0054] In some alternative embodiments, please continue to refer to Figure 4The transverse cross-sectional profile of one side surface of the hull 10 (i.e., the aforementioned first surface) is an arc-shaped second profile line 101. The second profile line 101 aligns with the first profile line 121, and the tangent line of the second profile line 101 near one end of the first profile line 121 is the first tangent line L1, while the tangent line of the first profile line 121 near one end of the second profile line 101 is the second tangent line. The first tangent line L1 coincides with the second tangent line. This arrangement allows for a smooth transition between the first surface of the hull 10 and the first arc-shaped chamfer 12, preventing the formation of protruding edges at the connection between the first arc-shaped chamfer 12 and the first surface, which could affect the fluid flow field and the hull 10's profile. This further reduces vibration and noise generation, ensuring the propulsion efficiency of the bow thruster system.

[0055] For example, the mounting cylinder 1 has an outlet edge 13 extending to the other side surface (i.e., the second surface) of the hull 10. The outlet edge 13 is provided with a second arc-shaped chamfer 14, that is, the corner of the outlet edge 13 is a rounded chamfer. The second arc-shaped chamfer 14 is used to guide fluid out of the mounting cylinder 1, and when the fluid passes through the second arc-shaped chamfer 14, it comes into contact with the second arc-shaped chamfer 14 to reduce the increase in vibration caused by the generation of eddies.

[0056] In this embodiment, by setting the first arc-shaped chamfer 12 and the second arc-shaped chamfer 14, the flow of fluid in the mounting cylinder 1 is improved and optimized, reducing the probability and amount of fluid separation from the inner wall of the mounting cylinder 1. Fluid separation can lead to backflow and blockage. Therefore, this embodiment reduces fluid separation, which reduces the torque fluctuation of the propeller 200. On the one hand, it reduces the damage to the propeller 200 caused by torque fluctuation and extends the service life of the propeller 200. On the other hand, it reduces vibration and noise levels.

[0057] Further optional, such as Figure 4 As shown, the transverse contour line of the second arc-shaped chamfer 14 is the third contour line 141. The third contour line 141 is arc-shaped, and the tangent of the third contour line 141 near the inner wall of the mounting cylinder 1 is parallel to the axis of the mounting cylinder 1. This allows the second arc-shaped chamfer 14 to smoothly transition with the inner wall of the mounting cylinder 1, thereby preventing the formation of protruding edges at the connection between the second arc-shaped chamfer 14 and the inner wall of the mounting cylinder 1, which could affect the fluid flow field. This further reduces vibration and noise generation, ensuring the propulsion efficiency of the bow thruster system. In this embodiment, the longitudinal contour line of the second arc-shaped chamfer 14 is a ring.

[0058] In some optional embodiments, the transverse cross-sectional profile of the other side surface of the hull 10 (i.e., the aforementioned second surface) is an arc-shaped fourth profile line 102. The transverse cross-sectional profile of the outlet edge 13 is a third profile line 141. The fourth profile line 102 aligns with the third profile line 141, and the tangent line of the fourth profile line 102 near one end of the third profile line 141 is the third tangent line L2. The tangent line of the third profile line 141 near one end of the fourth profile line 102 is the fourth tangent line, and the third tangent line L2 coincides with the fourth tangent line. This arrangement allows for a smooth transition between the second surface of the hull 10 and the second arc-shaped chamfer 14, thereby preventing the formation of protruding edges at the connection between the second arc-shaped chamfer 14 and the second surface, which could affect the fluid flow field and the hull 10's profile. This further reduces vibration and noise generation, ensuring the propulsion efficiency of the bow thruster system.

[0059] In some alternative embodiments, such as Figure 5 As shown, the bow thruster mounting device also includes a first guide member. The first guide member is streamlined and is disposed on the inner wall of the mounting cylinder 1, with one end extending to the inlet edge 11. The first guide member is used to guide the fluid entering the mounting cylinder 1, thereby further reducing the probability of the fluid downstream of the first guide member separating from the inner wall of the mounting cylinder 1, reducing the backflow caused by fluid separation and the probability of blockage, and reducing the torque fluctuation of the propeller 200, thereby further reducing vibration and noise.

[0060] For example, the first guide member may be annular and disposed on the inner wall of the mounting cylinder 1, or multiple first guide members may be provided, with multiple first guide members spaced apart along the circumference of the mounting cylinder 1.

[0061] For example, when the mounting cylinder 1 has an outlet edge 13 extending to the other side surface of the hull 10, the bow thrust mounting device further includes a second flow guide (not shown in the figure). The second flow guide is streamlined and disposed on the inner wall of the mounting cylinder 1 for guiding the fluid flow, and one end of the second flow guide extends to the outlet edge 13. The cooperation between the first flow guide and the second flow guide can further improve the flow field distribution.

[0062] Secondly, this embodiment provides a design method for a bow thruster mounting device, used to design the bow thruster mounting device of the first aspect, wherein the design method for the bow thruster mounting device includes the following steps:

[0063] S1. An mounting cylinder 1 is formed on the hull 10. The mounting cylinder 1 is disposed through the hull 10 in a preset direction, and the mounting cylinder 1 has an opening extending to the outer surface of one side of the hull 10.

[0064] S2. Chamfer the opening to form an inlet edge 11 with a first arc chamfer 12.

[0065] In step S1, the mounting cylinder 1 can be assembled onto the hull 10, or the mounting cylinder 1 can be directly formed on the hull 10. This embodiment does not limit this.

[0066] In step S2, a chamfering tool can be used to chamfer the mounting cylinder 1 to obtain the inlet edge 11.

[0067] The design method of the bow thruster installation device provided in this embodiment features an installation cylinder 1 with an inlet edge 11 extending to the outer surface of one side of the hull 10. The inlet edge 11 is provided with a first arc-shaped chamfer 12, which is used to guide fluid into the installation cylinder 1. The inlet edge 11 is designed without protruding ridges, thus optimizing the inlet edge 11. This reduces the separation of fluid from the inner wall of the installation cylinder 1 under the action of the inlet edge 11, ensuring the propulsion efficiency of the bow thruster system. Since the fluid does not separate from the inner wall of the installation cylinder 1, the flow field is more uniform. The non-uniformity of the flow field is the main source of vibration and noise. Therefore, this embodiment also reduces harmful vibration and noise, ensuring the normal operation of shipboard equipment and personnel, as well as personnel comfort.

[0068] Thirdly, this embodiment provides a bow thruster system, including a bow thruster mounting device as described in the first aspect, or a bow thruster mounting device designed according to the design method of the bow thruster mounting device described in the second aspect.

[0069] like Figure 3 As shown, the bow thruster system also includes a power unit 100 and a propeller 200. The power unit 100 is installed in the bow thruster mounting device and drives the propeller 200 to rotate. The propeller 200 is housed within the mounting cylinder 1. In this embodiment, the power unit 100 can be an electric motor or similar device; this embodiment is not limited to this.

[0070] In some alternative embodiments, at least a portion of the power device 100 is disposed within the mounting cylinder 1. For example, the power device 100 includes a mounting base located within the mounting cylinder 1, and the corners of the portion of the power device 100 located within the cylinder (i.e., the mounting base) are provided with rounded chamfers to avoid the problem of excessive eddies caused by the 90-degree corners affecting the flow field of the fluid, thereby further reducing vibration and noise.

[0071] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A bow thruster mounting device for mounting the propeller (200) of a bow thruster system, characterized in that, The device includes an installation cylinder (1) which extends through the hull (10) in a predetermined direction. The installation cylinder (1) has an inlet edge (11) extending to the outer surface of one side of the hull (10). The inlet edge (11) is provided with a first arc-shaped chamfer (12), which is used to guide fluid into the installation cylinder (1). The transverse contour line of the first arc chamfer (12) is the first contour line (121). The first contour line (121) is arc-shaped. The tangent of the first contour line (121) near the inner wall of the mounting cylinder (1) is parallel to the axis of the mounting cylinder (1). The transverse cross-sectional profile of one side surface of the hull (10) is an arc-shaped second profile line (101). The second profile line (101) is connected to the first profile line (121), and the tangent of the second profile line (101) near one end of the first profile line (121) is the first tangent line (L1). The tangent of the first profile line (121) near one end of the second profile line (101) is the second tangent line. The first tangent line (L1) coincides with the second tangent line.

2. The bow thruster mounting device according to claim 1, characterized in that, The hull (10) is provided with mounting holes, and the mounting cylinder (1) is installed in the mounting holes. The first port of the mounting cylinder (1) is located on the first surface of the hull (10), and the surface where the first port is located is coplanar with the first surface. The second port of the mounting cylinder (1) is located on the second surface of the hull (10), and the surface where the second port is located is coplanar with the second surface. Alternatively, a portion of the hull (10) may form the mounting cylinder (1).

3. The bow thruster mounting device according to claim 1, characterized in that, The horizontal contour line of the first arc chamfer (12) is the first contour line (121), and the radius of the circle containing the first contour line (121) is 250mm to 350mm.

4. The bow thruster mounting device according to claim 1, characterized in that, The mounting cylinder (1) has an outlet edge (13) extending to the other side surface of the hull (10), and the outlet edge (13) is provided with a second arc-shaped chamfer (14) for guiding fluid out of the mounting cylinder (1).

5. The bow thruster mounting device according to claim 4, characterized in that, The transverse contour line of the second arc chamfer (14) is the third contour line (141). The third contour line (141) is arc-shaped. The tangent of the third contour line (141) near the inner wall of the mounting cylinder (1) is parallel to the axis of the mounting cylinder (1). The transverse cross-sectional profile of the other side surface of the hull (10) is an arc-shaped fourth profile line (102). The fourth profile line (102) is connected to the third profile line (141), and the tangent of the fourth profile line (102) near one end of the third profile line (141) is the third tangent line (L2). The tangent of the third profile line (141) near one end of the fourth profile line (102) is the fourth tangent line. The third tangent line (L2) coincides with the fourth tangent line.

6. The bow thruster mounting device according to claim 1, characterized in that, The bow thruster installation device also includes a first guide member, which is streamlined and disposed on the inner wall of the installation cylinder (1), with one end extending to the inlet edge (11). The mounting cylinder (1) has an outlet edge (13) extending to the other side surface of the hull (10). The bow thrust mounting device also includes a second guide member, which is streamlined and disposed on the inner wall of the mounting cylinder (1), with one end extending to the outlet edge (13).

7. A design method for a bow thruster mounting device, used to design a bow thruster mounting device as described in any one of claims 1-6, characterized in that, The design method for the bow thruster mounting device includes the following steps: An mounting cylinder (1) is formed on the hull (10), the mounting cylinder (1) is disposed through the hull (10) in a predetermined direction, and the mounting cylinder (1) has an opening extending to the outer surface of one side of the hull (10); The opening is chamfered to form an inlet edge (11) with a first arc chamfer (12).

8. A bow thruster system, characterized in that, Includes the bow thruster mounting device as described in any one of claims 1-6, or includes the bow thruster mounting device designed according to the design method of the bow thruster mounting device according to claim 7; The bow thruster system also includes a power unit (100) and a propeller (200). The power unit (100) is installed in the bow thruster mounting device and is used to drive the propeller (200) to rotate. The propeller (200) is disposed inside the mounting cylinder (1).

9. The bow thruster system according to claim 8, characterized in that, At least a portion of the power device (100) is disposed within the mounting cylinder (1), and the corners of the portion of the power device (100) located within the mounting cylinder (1) are provided with rounded chamfers.

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