shallow-draft high-speed catamaran

Abstract

The application relates to a shallow-draft high-speed twin-hull ship, which comprises a ship body, the ship body comprises two pieces, the two pieces are connected through a connecting bridge; the piece comprises a wave-piercing bow, a round-bilge ship middle part and a square stern which are connected in sequence and smoothly transitioned; the bottom surface of the wave-piercing bow is a deep V-shaped line type, the front end of the wave-piercing bow comprises a pointed upper bow and a lower bow; the cross-sectional area of the wave-piercing bow gradually increases from front to back; the left and right sides of the front part of the piece are provided with concave semi-small waterline line type surfaces, the depth of the concave semi-small waterline line type surfaces gradually decreases from front to back; the semi-small waterline line type surfaces are located at the designed waterline height of the ship body; the design can simultaneously consider the routes of different navigation areas such as near-shore shoal, coastal and offshore navigation areas; the propeller can be guaranteed not to touch the bottom under the condition that the water depth is 2 meters at low tide, the navigation safety of the shallow-draft working condition is ensured, the seakeeping performance, the navigability and the passenger comfort of the ship are improved while the rapidity is ensured.

Description

Technical Field

[0001] This invention relates to the field of marine technology, specifically to a shallow-draft high-speed catamaran. Background Technology

[0002] With the rapid development of domestic shipbuilding, its scale, output, and demand for maritime transport have also grown rapidly. In particular, the rise of industries with high speed requirements, such as wind power operation and maintenance and high-speed passenger transport, has increased the demand for high-speed vessels. Compared to monohull vessels, catamarans have advantages such as lower wave-making resistance and higher stability, making them highly favored in the high-speed vessel market. To adapt to the high sea state requirements of coastal and near-shore waters, while maintaining good speed, vessels also need to have good wind and wave resistance and passenger comfort, reducing seasickness rates, especially in shallow waters with large tidal ranges and limited draft.

[0003] Depending on the conditions of different waters in China, there are specific requirements for shallow-draft high-speed catamaran vessels. For example, in the waters of Shangchuan and Xiachuan Islands in Taishan, Guangdong, and Rudong, Jiangsu, a large portion of these waters has a depth of about 2 meters at low tide. Therefore, shallow-draft high-speed catamarans are needed to meet transportation needs during low water levels. Several new vessels under 30 meters in length have been built in these areas, including monohull and catamaran vessels. While monohull vessels can meet the shallow-draft requirements, their speed is relatively lower than that of catamarans with the same main engine power. Although catamarans have higher speeds, their draft is greater than that of monohull vessels, and their navigation is more difficult to control at high speeds, frequently resulting in situations such as stern listing of more than 2 degrees (a draft difference of approximately 0.9 meters between bow and stern) and propeller bottoming. Therefore, their overall operational performance is not ideal, necessitating a product upgrade. Summary of the Invention

[0004] The purpose of this invention is to address the above-mentioned shortcomings by providing a shallow-draft high-speed catamaran suitable for maritime operations in nearshore shoals, coastal and offshore navigation areas, especially in shallow waters with large tidal range differences and limited draft.

[0005] The technical solution adopted by the present invention to solve the technical problem is to provide a shallow draft high-speed catamaran, including a hull, wherein the hull includes two symmetrically arranged plates, and the two plates are connected by a connecting bridge.

[0006] The body comprises a wave-piercing bow, a round bilge midship, and a square stern, which are connected in a smooth transition.

[0007] The bottom surface of the wave-piercing bow is a deep V-shape, and the front end of the wave-piercing bow includes a pointed upper bow and a lower bow.

[0008] The cross-sectional area of ​​the wave-piercing bow gradually increases from front to back;

[0009] The front part of the sheet body is provided with a semi-waterline surface type surface with an inner recess on the left and right sides, and the depth of the inner recess gradually decreases from front to back.

[0010] The semi-waterline surface type surface is located at the designed waterline height of the ship body.

[0011] Further, the length of the wave-piercing bow is 0.1-0.2 times the length of the ship;

[0012] The length of the round-bilge ship is 0.6-0.8 times the length of the ship, and the width of the round-bilge ship is 0.1-0.25 times the width of the ship;

[0013] The length of the square stern is 0.1-0.2 times the length of the ship, and the width of the square stern is 0.25-0.3 times the width of the ship.

[0014] Further, the bottom plate and the side plate of the round-bilge ship are smoothly connected by a circular arc, and the radius of the circular arc is 0.03-0.06 times the width of the ship;

[0015] The included angle between the bottom plate and the side plate of the square stern is 90-125°.

[0016] Further, the upper bow lower side surface, the lower bow upper side surface, and the lower bow lower side surface are all inclined surfaces;

[0017] The included angle between the lower bow lower side surface and the baseline of the ship body is 35-40°, and the included angle between the upper bow lower side surface and the upper bow upper side surface is 55-60°.

[0018] Further, the cross section of the square stern gradually transitions from a round bilge to a corner bilge from front to back.

[0019] Further, the square stern lower side surface is provided with an inner recessed propeller accommodation slot in the rear part, and a propeller is installed in the middle part of the propeller accommodation slot.

[0020] Further, the propeller shaft is installed at an angle of 5-8°.

[0021] Further, the lowest point of the propeller blade is located below the baseline of the ship body, and the distance between the lowest point of the propeller blade and the baseline of the ship body is 120-150 mm.

[0022] Further, the distance between the top end of the propeller accommodation slot and the propeller blade is 0.15-0.2 times the diameter of the propeller blade, and the distance between the two bottom ends of the propeller accommodation slot is 1.4-1.5 times the diameter of the propeller blade.

[0023] Further, the height of the front deck surface of the ship body is greater than the height of the rear deck surface, and the front end surface of the connecting bridge is an inclined surface and the lower side surface is a curved surface.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] The fast speed of the wave-piercing bow deep V ship type, and the seakeeping of the small waterplane ship type are considered;

[0026] The round bilge ship middle and square stern make the ship body have a larger square coefficient, so that the floating center of the ship is moved backward, and the tail is obviously lifted when the ship sails at high speed, and has a more stable sailing state;

[0027] The recessed design of the propeller accommodation groove can improve the propeller propulsion efficiency and reduce the maximum draft of the ship;

[0028] It is suitable for offshore shallow, coastal and offshore navigation, especially in shallow waters with large high-low tidal difference and limited draft, especially in the case of 2 meters of water depth at low tide, which can ensure that the propeller does not touch the bottom and ensure the safety of the ship sailing in shallow water conditions, ensure the rapidity of the ship, and improve the seakeeping, seaworthiness and passenger comfort of the ship.

[0029] The ship body in the design can achieve higher speed than the small waterplane ship type, and better seakeeping than the conventional deep V angle ship type, while balancing the design draft and high-speed sailing state of the ship, meeting the safety and high-speed sailing requirements in shallow waters.

[0030] The design combines the semi-small waterplane deep V bow, round bilge ship middle and square stern line type, and the recessed propeller accommodation groove design and propeller axis angle control, maintains the sailing state of the ship at a high speed between 0.2-0.4 degrees of stern rake; the ship body can simultaneously consider the routes in different navigation areas such as nearshore shallow, coastal and offshore navigation areas, and can meet various operation requirements, especially in the case of 2 meters of water depth at low tide, which can ensure that the propeller does not touch the bottom and ensure the safety of the ship sailing in shallow water conditions, ensure the rapidity of the ship, and improve the seakeeping, seaworthiness and passenger comfort of the ship. BRIEF DESCRIPTION OF DRAWINGS

[0031] The present invention will be further described below in combination with the drawings.

[0032] Figure 1 It is a schematic diagram of the ship body structure;

[0033] Figure 2 It is a perspective view of the front end direction of the ship body;

[0034] Figure 3 It is a perspective view of the rear end direction of the ship body;

[0035] Figure 4 It is a schematic diagram of the bow line type;

[0036] Figure 5 It is a schematic diagram of the middle line type of the ship;

[0037] Figure 6 A schematic view of the lines of the stern;

[0038] Figure 7 A schematic view of the flow guide of the bow raised foredeck.

[0039] In the figure:

[0040] 1 - wave-piercing bow; 2 - round bilge midship; 3 - square stern; 4 - propeller; 5 - foredeck surface; 6 - afterdeck surface; 7 - upper bow; 8 - lower bow; 9 - semi-venetian lines surface; 10 - propeller accommodation slot; 11 - connecting bridge. DETAILED DESCRIPTION

[0041] The preferred embodiments of the present application will be described in more detail below, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art. It should be understood that the specific examples described herein are merely used to explain the present application and should not be used to limit the present application.

[0042] For the water area with a large part of the water depth of about 2 meters at low tide, although the existing catamaran has high speed, its draft is larger than that of monohull, and the ship's sailing state is difficult to control at high speed, often with more than 2 degrees of stern rake (the difference between the bow and stern drafts is about 0.9m), and the propeller 4 touches the bottom, etc., so the overall operation is not ideal, and there is a need for product upgrading.

[0043] To solve the above problems, the embodiment provides a shallow-draft high-speed catamaran, which is suitable for offshore shallow water, coastal and offshore navigation areas, especially shallow water areas with large difference between high and low tides and limited draft.

[0044] As shown in Figures 1-7 A shallow-draft high-speed catamaran, comprising a hull, the hull comprises two pieces arranged symmetrically left and right, the two pieces are connected through a connecting bridge 11;

[0045] The piece comprises a wave-piercing bow 1, a round bilge midship 2 and a square stern 3 connected smoothly in sequence;

[0046] The bottom surface of the wave-piercing bow 1 is a deep V-shaped line, the front end of the wave-piercing bow 1 comprises a sharp upper bow 7 and a lower bow 8, the upper bow 7 and the lower bow 8 form a Z-shaped wave-piercing body, which can prolong the designed waterline, reduce the wave-making resistance during high-speed sailing of the ship, increase the longitudinal volume, and more reasonably distribute the reserve of buoyancy, so that the sailing state is more stable;

[0047] The cross-sectional area of the wave-piercing bow 1 gradually increases from front to back;

[0048] The left and right sides of the front part of the sheet body are provided with a concave semi-waterline profile 9, and the depth of the concave gradually decreases from front to back;

[0049] The semi-waterline profile 9 is located at the designed waterline height of the hull;

[0050] In the design, the front end of the ship adopts a deep V hull to obtain stability and minimum rolling in navigation, and a concave semi-waterline profile is arranged near the designed waterline height at the front part of the sheet body according to the need of improving the sea-keeping performance, so that the ship type has the rapidity of the deep V ship type and the sea-keeping performance of the small waterline ship type. In actual application, the depth of the concave can be appropriately adjusted according to the need of arranging the bottom tank of the ship, so as to balance the arrangement of various functional cabins of the ship;

[0051] In the design, the circular bilge midship 2 and the square stern 3 are adopted, so that the hull has a larger square coefficient, can provide larger displacement and buoyancy, and has a shallower draft. Due to the increase of the buoyancy of the mid stern, the floating center of the ship moves backward, and the tail is obviously lifted in high-speed navigation, so that the ship has a more stable navigation state;

[0052] The hull in the design can obtain higher navigation speed than the small waterline ship type, and better sea-keeping performance than the conventional deep V angle ship type, while balancing the designed draft and high-speed navigation state of the ship, and meeting the safety and high-speed navigation requirements in shallow sea areas.

[0053] The design combines the semi-waterline deep V bow, the circular bilge midship 2 and the square stern line type, and combines the concave propeller accommodation groove 10 design and the propeller axis angle control, so as to maintain the navigation state of the ship at 0.2-0.4 degrees of stern inclination under high speed. The hull can simultaneously consider the navigation route in different navigation areas such as nearshore shoal, coastal and offshore navigation areas, can meet various operation requirements, especially can ensure that the propeller 4 does not touch the bottom under the condition of water depth of 2 meters in low tide, ensures the navigation safety in shallow draft condition, ensures the rapidity of the ship, and improves the sea-keeping performance, seaworthiness and passenger comfort of the ship.

[0054] In the embodiment, the length of the wave-piercing bow 1 is 0.1-0.2 times the length of the ship;

[0055] The length of the circular bilge midship 2 is 0.6-0.8 times the length of the ship, and the width of the circular bilge midship 2 is 0.1-0.25 times the width of the ship;

[0056] The length of the square stern 3 is 0.1-0.2 times the length of the ship, and the width of the square stern 3 is 0.25-0.3 times the width of the ship.

[0057] In the embodiment, the bottom plate and the side plate of the circular bilge midship 2 are smoothly connected through a circular arc, and the radius of the circular arc is 0.03-0.06 times the width of the ship;

[0058] The included angle between the bottom plate and the side plate of the square stern 3 is 90-125°;

[0059] Compared with the round bilge ship type, the displacement of the stern line shape adjustment area increases by 1-3%.

[0060] In the embodiment, the upper bow 7 lower side, the lower bow 8 upper side, and the lower bow 8 lower side are all inclined surfaces.

[0061] The included angle between the lower bow 8 lower side and the baseline of the hull is 35-40°, and the included angle between the upper bow 7 lower side and the upper bow 7 upper side is 55-60°.

[0062] Compared with the vertical bow ship type, the comprehensive resistance of the hull is reduced by 2-3%.

[0063] In the embodiment, the square stern 3 lower side rear part is provided with a concave propeller accommodation slot 10, and a propeller 4 is installed in the middle of the propeller accommodation slot 10. The concave designed propeller accommodation slot 10 can ensure to reduce the installation angle of the propeller axis, and the propeller shaft of the propeller 4 is installed at an angle of 5-8°. Because the angle is small, the propeller 4 thrust is more output to the stern side, reducing the downward propulsion loss, and the overall propulsion efficiency is higher. At the same time, the small installation angle combined with the concave designed propeller accommodation slot 10 can effectively improve the installation position of the propeller 4, so as to reduce the maximum draft of the ship. The design can ensure that the ship can operate normally at low tide, especially in specific routes such as the Chuan Island area. During the period of low tide, other propellers 4 touch the bottom and run aground, and the ship can still operate normally, creating obvious economic benefits.

[0064] In the embodiment, the lowest point of the propeller blade of the propeller 4 is below the baseline of the hull, and the distance between the lowest point of the propeller blade and the baseline of the hull is 120-150 mm. Under full load navigation working conditions, the maximum draft containing the propeller 4 is less than 1.3 m, so the ship fully has the basis of safe and high-speed navigation in the shallow sea area with a water depth of 2 m.

[0065] In the embodiment, the distance between the top end of the propeller accommodation slot 10 and the propeller blade is 0.15-0.2 times the diameter of the propeller blade, and the distance between the two bottom ends of the propeller accommodation slot 10 is 1.4-1.5 times the diameter of the propeller blade.

[0066] In the embodiment, the cross section of the square stern 3 gradually transitions from the round bilge to the angle bilge from front to back, which can maximize the reduction of the influence of the hull on the efficiency of the propeller 4 in combination with the customized propeller accommodation slot 10. The square stern 3 increases the underwater buoyancy and displacement, further lifts the ship, thereby reducing the draft, the heave, and the roll of the ship, achieving better seakeeping performance, and improving the comfort of passengers.

[0067] In the present embodiment, as shown in Figure 7 The height of the front deck surface 5 is greater than the height of the rear deck surface 6, and the front deck surface 5 is raised to reduce the impact of waves on the bottom of the connecting bridge 11. The front end surface of the connecting bridge 11 is inclined, and the lower surface is curved. The combination of the inclined front end surface and the curved bottom surface has a streamlined structure, which has better flow guiding effect and smaller resistance than a flat vertical bow when the ship sails at high speed against the wind or waves, and can also avoid vibration caused by turbulence.

[0068] In actual application, the designed waterline length of the sheet body is about 27.5 m, and the maximum draft in the flat floating state after the appendages such as the propeller 4 and the rudder blade is 1.24 m. When the ship sails at a high speed of 24-26 knots, the actual measured trim of the ship is 0.2-0.4 degrees (the maximum bow-stern draft difference is -0.2 m). Therefore, under the full load sailing condition, since the buoyancy center of the present ship body is located rearward of the ship, it is known that the maximum draft including the propeller 4 is less than 1.4 m after considering the influence of the trim of the ship. Therefore, the ship completely has the ability to sail safely and at high speed in shallow sea areas with a water depth of 2 m.

[0069] The relative arrangement of parts and steps, numerical expressions, and numerical values set forth in the embodiments are not intended to limit the scope of the present application, unless otherwise specifically stated. In all of the examples shown and discussed herein, any specific value should be interpreted as merely an example, and not as a limitation. Thus, other examples of the example embodiments can have different values. It should be noted that like numbers and letters refer to like items, and therefore, once an item is defined, no further discussion is required for it in subsequent instances.

[0070] In the description of the present application, it should be understood that the orientation or position relationship indicated by orientation words such as “front, rear, upper, lower, left, right”, “transverse, vertical, perpendicular, horizontal”, and “top, bottom” is generally based on the shown orientation or position relationship, and is only for the convenience of describing the present application and simplifying the description. Without the contrary indication, these orientation words do not indicate and imply that the indicated device or element must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the scope of protection of the present application; the orientation words “inner, outer” refer to the inner and outer of the contour of each component itself.

[0071] For the convenience of description, spatial relative terms such as “over”, “above”, “upper surface”, “upper” and the like can be used herein to describe the spatial positional relationship of features. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the described orientation.

[0072] In addition, it should be noted that the use of the terms "first", "second" and the like, to describe various elements, is merely intended to differentiate one element from another, and is not intended to limit the scope of the present application, unless otherwise specified.

[0073] If the present application discloses or involves mutually fixedly connected parts or structural members, unless otherwise specified, the fixed connection can be understood as: detachable fixed connection (for example, connected by bolts or screws), or as: non-detachable fixed connection (for example, riveting, welding), of course, the mutually fixed connection can also be replaced by an integral structure (obviously, except for the cases where integral forming process cannot be used).

[0074] The above preferred embodiments further illustrate the purpose, technical solutions and advantages of the present application, and it should be understood that the above description is only for the preferred embodiments of the present application, and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A shallow-draft high-speed catamaran comprising a hull, the hull comprising two left-right symmetrical hulls connected by a connecting bridge. Characterized in that: the hulls comprise a wave-piercing bow, a round-bilge midship and a square stern connected in sequence and smoothly transitioned; the bottom surface of the wave-piercing bow is a deep V-line type, and the front end of the wave-piercing bow comprises a pointed upper bow and a lower bow; the cross-sectional area of the wave-piercing bow gradually increases from front to back; the left and right sides of the front part of the hull are provided with a concave semi-small waterplane line type surface, and the depth gradually decreases from front to back; the semi-small waterplane line type surface is located at the designed waterline height of the hull; the bottom plate and the side plate of the round-bilge midship are smoothly transitioned by an arc; the cross-section of the square stern gradually transitions from a round bilge to an angle bilge from front to back.

2. The shallow-draft high-speed catamaran according to claim 1, characterized in that: The length of the wave-piercing bow is 0.1-0.2 times the length of the ship; the length of the round-bilge midship is 0.6-0.8 times the length of the ship, and the width of the round-bilge midship is 0.1-0.25 times the width of the ship; the length of the square stern is 0.1-0.2 times the length of the ship, and the width of the square stern is 0.25-0.3 times the width of the ship.

3. The shallow-draft high-speed catamaran according to claim 2, characterized in that: The radius of the arc is 0.03-0.06 times the width of the ship; the included angle between the bottom plate and the side plate of the square stern is 90-125°.

4. The shallow-draft high-speed catamaran according to claim 1, characterized in that: The lower side of the upper bow, the upper side of the lower bow, and the lower side of the lower bow are all inclined surfaces; the included angle between the lower side of the lower bow and the baseline of the hull is 35-40°, and the included angle between the lower side of the upper bow and the upper side of the upper bow is 55-60°.

5. The shallow-draft high-speed catamaran of claim 1, characterized in that: The rear part of the lower side of the square stern is provided with a concave propeller accommodation slot, and a propeller is installed in the middle of the propeller accommodation slot.

6. A shallow-draft high-speed catamaran according to claim 5, characterized in that: The propeller shaft is installed obliquely, and the installation angle is 5-8°.

7. A shallow-draft high-speed catamaran according to claim 6, characterized in that: The lowest point of the propeller blade is below the baseline of the hull, and the distance between the lowest point of the propeller blade and the baseline of the hull is 120-150 mm.

8. The shallow-draft high-speed catamaran according to claim 6, characterized in that: The distance between the top end of the propeller accommodation slot and the propeller blade is 0.15-0.2 times the diameter of the propeller blade, and the distance between the two bottom ends of the propeller accommodation slot is 1.4-1.5 times the diameter of the propeller blade.

9. A shallow-draft high-speed catamaran according to any one of claims 1-8, characterized in that: The height of the front deck surface of the hull is greater than the height of the rear deck surface, and the front end surface of the connecting bridge is inclined and the lower side is curved.

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