A multi-curvature optimized drag-reducing lateral thruster flow channel
By designing a drag-reducing lateral thruster guide channel with optimized curvature, the problems of resistance and structural strength of ships with large curvature hull lines were solved, achieving drag reduction and improved structural safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- DALIAN SHIPBUILDING INDUSTRY CO LTD
- Filing Date
- 2023-08-21
- Publication Date
- 2026-05-29
AI Technical Summary
In the existing technology, the design of the lateral thruster guide channel cannot effectively reduce the resistance of ships with large curvature lines, resulting in damage to the structural strength and affecting the safety and performance of the ship.
A multi-curvature optimized drag-reducing lateral thruster guide channel is designed, adopting a similar horn-mouth shape. Different chamfer angles are designed at different positions according to the water flow direction and the lateral gradient at the end of the opening. Combined with multi-curvature transition, the guide channel structure is optimized.
The reduction in structural cutting volume preserved structural strength, lowered ship resistance by 3.2%, and improved ship safety and performance.
Smart Images
Figure CN117284463B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of ship design and manufacturing, and more specifically, to the design of propeller guide channels in ship hulls. Background Technology
[0002] Lateral thrusters are increasingly being used on the bow of various large ships to address the increasing difficulty of entering and leaving ports as ships grow larger; and on ships that require dynamic positioning to provide lateral positioning functionality.
[0003] Lateral thrusters located at the bow of a ship experience significant drag due to the large change in the ship's bow profile, resulting in substantial resistance at the thruster openings and impacting the ship's performance. The guide channels in the lateral thrusters can effectively reduce vortices and decrease the drag at the thruster openings. For example... Figures 1-6 As shown, the conventional guide channel design of the lateral thruster 1 uses a single chamfer angle to design a simple conical guide channel, which has a very limited effect on reducing friction. Moreover, as... Figures 7-10 As shown, if a ship with a large curvature hull uses this type of single-bevel angle guide channel, it will result in a large amount of structure being cut away, damaging the ship's structural strength and seriously affecting its safety. In the figure, the labels are: lateral thruster 1, opening 5, guide channel 6, lateral thruster pipe 11, X is the horizontal mid-section direction, Y is the vertical mid-section direction, I is the uppermost end of the guide channel, II is the lowermost end of the guide channel, III is the frontmost end of the guide channel, and IV is the rearmost end of the guide channel.
[0004] Designing a flow channel for ships with large curvature hulls and reducing resistance is a challenging problem that needs to be solved. Summary of the Invention
[0005] Based on the large curvature of the ship's hull, this invention designs different chamfer angles at different positions according to the water flow direction and the lateral gradient at the opening end. By applying multi-curvature transition and optimization, the invention innovatively designs a drag-reducing lateral thruster guide channel with multi-curvature optimization, aiming to reduce ship resistance.
[0006] To achieve the above objectives, the present invention provides 1. a multi-curvature optimized drag-reducing lateral thruster guide groove, wherein the lateral thruster opening is designed as a guide groove in the form of a horn-shaped mouth.
[0007] In the preferred embodiment, the foremost edge of the guide channel and the lateral thruster pipe is designed with a maximum chamfer angle C1, where 150° ≥ C1 ≥ 90°; the foremost curved surface of the guide channel and the lateral thruster pipe is designed with a minimum chord length D1, where D1 ≤ R1 / 3, and R1 is the radius of the lateral thruster pipe; the foremost edge of the mid-section of the guide channel and the lateral thruster pipe is designed with a chamfer angle E1, where E1 ≤ C1; the foremost curved surface of the mid-section of the guide channel and the lateral thruster pipe is designed with a chord length F1, where D1 ≤ F1.
[0008] The final end of the guide channel and the lateral thruster pipe is designed with a minimum chamfer angle C2, 60°≤C2≤90°; the curved surface of the final end of the guide channel and the lateral thruster pipe is designed with a maximum chord length D2, D2≥R1; the rear end of the mid-section of the guide channel and the lateral thruster pipe is designed with a chamfer angle E2, C2≤E2; the curved surface of the rear end of the mid-section of the guide channel and the lateral thruster pipe is designed with a chord length F2, F2≤D2.
[0009] The uppermost end of the guide channel and the lateral thruster pipe is designed with a chamfer angle C3, C3 = 90°; the uppermost curved surface of the guide channel 6 and the lateral thruster pipe is designed with a chord length D3, D3 ≥ D1; the upper end of the mid-section of the guide channel and the lateral thruster pipe is designed with a chamfer angle E3, E3 ≤ C3; the upper curved surface of the mid-section of the guide channel and the lateral thruster pipe is designed with a chord length F3, F3 ≤ D3.
[0010] The bottom of the guide channel and the lateral thruster pipe is designed with a chamfer angle C4, C4 = 90°; the bottom curved surface of the guide channel and the lateral thruster pipe is designed with a chord length D4, D4 ≥ D1; the bottom of the middle section of the guide channel and the lateral thruster pipe is designed with a chamfer angle E4, C4 ≤ E4; the bottom curved surface of the middle section of the guide channel and the lateral thruster pipe is designed with a chord length F4, F4 ≥ D4.
[0011] In a preferred embodiment, the opening of the lateral thruster is covered by an openwork grille. The openwork grille is designed with a cross-shaped structure; the main structure of the openwork grille is in the form of flat iron; the direction of the main structure is the streamline direction, and its position is outside the opening; the main structure spacing is G, where G ≤ R1 / 5. The secondary structure of the openwork grille is in the form of cylinders, the direction of the secondary structure is perpendicular to the streamline direction F, and its position is inside the opening; the secondary structure spacing is H, where H ≤ R1 / 3.
[0012] Based on the large curvature of the ship's hull, this invention designs different chamfer angles at different positions according to the water flow direction and the lateral gradient at the orifice end. By applying multi-curvature transitions and optimizations, it innovatively designs a drag-reducing lateral thruster guide channel with multi-curvature optimization. The advantages of this invention are reduced structural cutting while maintaining structural strength and ensuring structural safety. Conventional solutions involve a longitudinal cutting length approximately 8 times the radius of the lateral thruster pipe, a lateral cutting length approximately 5 times the radius, and a height cutting length approximately 4 times the radius. This invention achieves a longitudinal cutting length approximately 4 times the radius of the lateral thruster pipe, a lateral cutting length approximately 2 times the radius, and a height cutting length approximately 3 times the radius, with a cutting area approximately 1 / 6 that of the conventional solution. According to CFD software calculations and comparisons, under specific ship speed conditions, the guide channel of this invention reduces the pressure near the lateral thruster orifice, reducing ship resistance by 3.2%. Attached Figure Description
[0013] Figure 1 This is a top view schematic diagram of the guide channel for a drag-reducing lateral thruster in an existing ship hull.
[0014] Figure 2 It is relative Figure 1 A side view diagram.
[0015] Figure 3 yes Figure 1 A magnified top view of a portion of point A in the middle.
[0016] Figure 4 yes Figure 1 A magnified side view of a portion of point A in the middle.
[0017] Figure 5 yes Figure 1 A magnified horizontal midsection top view of point A.
[0018] Figure 6 yes Figure 1 A magnified side view of the vertical midsection at point A.
[0019] Figure 7 This is a top view schematic diagram of the second type of drag-reducing lateral thruster guide channel in existing ship hull technology.
[0020] Figure 8 It is relative Figure 7 A side view diagram.
[0021] Figure 9 This is a top view schematic diagram of the third type of drag-reducing lateral thruster guide channel in existing ship hull technology.
[0022] Figure 10 It is relative Figure 9 A side view diagram.
[0023] Figure 11 It is relative Figure 7 A partially enlarged top view of point B of the flow guide groove of the present invention.
[0024] Figure 12 It is relative Figure 11 A partially enlarged side view of part B of the present invention.
[0025] Figure 13 It is relative Figure 11 A top view showing the streamlined direction of a portion of part B in this invention.
[0026] Figure 14 It is relative Figure 11 A magnified horizontal midsection top view at point B of this invention.
[0027] Figure 15 It is relative Figure 11 A magnified side view of part B in the present invention, showing the vertical streamline direction.
[0028] Figure 16 It is relative Figure 11 A partially enlarged mid-section side view at point B of the present invention.
[0029] Figure 17 This is a top view of the grille installed at point B of the present invention.
[0030] Figure 18 It is relative Figure 16 A side view diagram.
[0031] Figure 19 This is a schematic diagram of the pressure distribution when there is no guide channel, calculated by CFD software.
[0032] Figure 20 This is a schematic diagram of the pressure distribution of the guide channel in this invention calculated using CFD software. Detailed Implementation
[0033] like Figures 11-18 The multi-curvature optimized drag-reducing lateral thruster guide channel of the present invention includes a drag-reducing lateral thruster guide channel 6 and a drag-reducing lateral thruster perforated grid 7.
[0034] The opening 5 of the lateral thruster 1 is designed as a funnel-shaped guide channel 6 to avoid abrupt changes in structural geometry, prevent the generation of a large number of eddies, and reduce ship resistance. The guide channel 6 has a smooth surface with multiple chamfered angles and multiple curvatures. First, based on the streamline direction, the direction of the longest end of the guide channel is designed. In this invention, the direction of the longest end of the guide channel is consistent with the streamline direction. According to fluid simulation analysis, the guide channel's resistance is minimized when the direction of the longest end is consistent with the streamline direction. The intersections of the guide channel with the lateral thruster pipe 11 along the streamline direction and perpendicular to the streamline direction are determined as the foremost, last, uppermost, and lowermost ends of the guide channel, which are not the intersections of the length and height directions of a conventional guide channel.
[0035] In the diagram, M represents the streamline direction, i.e., the direction of water flow; N represents the direction perpendicular to the streamline. I is the uppermost end of the guide channel, II is the lowermost end of the guide channel, III is the frontmost end of the guide channel, and IV is the rearmost end of the guide channel.
[0036] The front end of the guide channel 6 and the lateral thruster pipe 11 is designed with a maximum chamfer angle C1, where 150° ≥ C1 ≥ 90°; the front end curved surface of the guide channel 6 and the lateral thruster pipe 11 is designed with a minimum chord length D1, where D1 ≤ R1 / 3, and R1 is the radius of the lateral thruster pipe 11; the front end of the mid-section of the guide channel 6 and the lateral thruster pipe 11 is designed with a chamfer angle E1, where E1 ≤ C1; the front end curved surface of the mid-section of the guide channel 6 and the lateral thruster pipe 11 is designed with a chord length F1, where D1 ≤ F1.
[0037] The rear end of the guide channel 6 and the lateral thruster pipe 11 is designed with a minimum chamfer angle C2, 60°≤C2≤90°; the curved surface of the rear end of the guide channel 6 and the lateral thruster pipe 11 is designed with a maximum chord length D2, D2≥R1; the rear end of the mid-section of the guide channel 6 and the lateral thruster pipe 11 is designed with a chamfer angle E2, C2≤E2; the curved surface of the rear end of the mid-section of the guide channel 6 and the lateral thruster pipe 11 is designed with a chord length F2, F2≤D2.
[0038] The uppermost end of the guide channel 6 and the lateral thruster pipe 11 is designed with a chamfer angle C3, C3 = 90°; the uppermost curved surface of the guide channel 6 and the lateral thruster pipe 11 is designed with a chord length D3, D3 ≥ D1; the upper end of the mid-section of the guide channel 6 and the lateral thruster pipe 11 is designed with a chamfer angle E3, E3 ≤ C3; the upper curved surface of the mid-section of the guide channel 6 and the lateral thruster pipe 11 is designed with a chord length F3, F3 ≤ D3.
[0039] The bottom of the guide channel 6 and the lateral thruster pipe 11 is designed with a chamfer angle C4, C4 = 90°; the bottom curved surface of the guide channel 6 and the lateral thruster pipe 11 is designed with a chord length D4, D4 ≥ D1; the bottom of the middle section of the guide channel 6 and the lateral thruster pipe 11 is designed with a chamfer angle E4, C4 ≤ E4; the bottom curved surface of the middle section of the guide channel 6 and the lateral thruster pipe 11 is designed with a chord length F4, F4 ≥ D4.
[0040] The lateral thruster opening grille can effectively prevent the lateral thruster pipe 11 from being blocked by large objects; the lateral thruster opening grille 7, which reduces stress, is designed with a cross structure; the main structure of the lateral thruster opening grille 7, which reduces stress, is in the form of flat iron, in the direction of the streamline, and is located outside the opening, with a main structure spacing of G, where G≤R1 / 5; the secondary structure of the lateral thruster opening grille 7, which reduces stress, is in the form of cylinder, in the direction perpendicular to the streamline, and is located inside the opening, with a secondary structure spacing of H, where H≤R1 / 3;
[0041] pass Figure 19 and Figure 20 Based on CFD software calculations and comparisons, under specific ship speed conditions, the flow guide channel of this invention reduces the pressure near the side thrust holes, thus reducing ship resistance by 3.2%. Through comparative model tests in a water tank, this invention can reduce ship resistance by 2%.
[0042] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
Claims
1. A drag-reducing lateral thruster guide channel with multi-curvature optimization, characterized in that, The side thruster (1) opening (5) is designed as a guide groove (6) similar to a horn mouth; The front end of the guide channel (6) and the lateral thruster pipe (11) is designed with the maximum chamfer angle C1, 150°≥C1≥90°; the front end curved surface of the guide channel (6) and the lateral thruster pipe (11) is designed with the minimum chord length D1, D1≤R1 / 3, R1 is the radius of the lateral thruster pipe (11); the front end of the middle section of the guide channel (6) and the lateral thruster pipe (11) is designed with the chamfer angle E1, E1≤C1; the front end curved surface of the middle section of the guide channel (6) and the lateral thruster pipe (11) is designed with the chord length F1, D1≤F1; The rear end of the guide channel (6) and the lateral thruster pipe (11) is designed with a minimum chamfer angle C2, 60°≤C2≤90°; the curved surface of the rear end of the guide channel (6) and the lateral thruster pipe (11) is designed with a maximum chord length D2, D2≥R1; the rear end of the middle section of the guide channel (6) and the lateral thruster pipe (11) is designed with a chamfer angle E2, C2≤E2; the curved surface of the rear end of the middle section of the guide channel (6) and the lateral thruster pipe (11) is designed with a chord length F2, F2≤D2; The uppermost end of the guide channel (6) and the lateral thruster pipe (11) is designed with a chamfer angle C3, C3=90°; the uppermost curved surface of the guide channel (6) and the lateral thruster pipe (11) is designed with a chord length D3, D3≥D1; the upper end of the cross section of the guide channel (6) and the lateral thruster pipe (11) is designed with a chamfer angle E3, E3≤C3; the upper curved surface of the cross section of the guide channel (6) and the lateral thruster pipe (11) is designed with a chord length F3, F3≤D3; The bottom of the guide channel (6) and the side thruster pipe (11) is designed with a chamfer angle C4, C4=90°; the bottom surface of the guide channel (6) and the side thruster pipe (11) is designed with a chord length D4, D4≥D1; the bottom of the middle section of the guide channel (6) and the side thruster pipe (11) is designed with a chamfer angle E4, C4≤E4; the bottom surface of the middle section of the guide channel (6) and the side thruster pipe (11) is designed with a chord length F4, F4≥D4.
2. The multi-curvature optimized drag-reducing lateral thruster guide channel according to claim 1, characterized in that, The opening of the side thruster (1) is covered by an open grid (7).
3. The multi-curvature optimized drag-reducing lateral thruster guide channel according to claim 2, characterized in that, The perforated grille (7) is designed with a cross structure.
4. The drag-reducing lateral thruster guide channel with multi-curvature optimization according to claim 2, characterized in that, The main structure of the perforated grid (7) is in the form of flat iron.
5. The multi-curvature optimized drag-reducing lateral thruster guide channel according to claim 4, characterized in that, The perforated grille (7) is configured with its main structure facing the streamline direction and its position being on the outside of the opening.
6. The multi-curvature optimized drag-reducing lateral thruster guide channel according to claim 5, characterized in that, The main structure of the perforated grid (7) has a spacing G, where G≤R1 / 5.
7. The multi-curvature optimized drag-reducing lateral thruster guide channel according to claim 2, characterized in that, The secondary structure of the perforated grille (7) is cylindrical.
8. The multi-curvature optimized drag-reducing lateral thruster guide channel according to claim 2, characterized in that, The secondary structure direction of the perforated grid (7) is perpendicular to the streamline direction F, and its position is inside the opening.
9. The multi-curvature optimized drag-reducing lateral thruster guide channel according to claim 2, characterized in that, The secondary structural spacing H of the perforated grid (7) is H≤R1 / 3.