A local flexible bottom structure for a planing boat

Abstract

The present invention discloses a local flexible bottom structure that absorbs and reduces impact energy by flexible deformation, including a flexible outer plate of the bottom, a flexible support, and an inner bottom plate; the outer plate of the bottom is a composite material outer plate that can withstand a certain intensity of water impact pressure and is arranged at the hydrodynamic stagnation point of the bottom; the hull should be folded inward according to the installation height of the flexible structure to form an inner bottom plate that is a continuous structure with the bottom plate; between the flexible outer plate and the inner bottom plate, a flexible support is arranged according to the distribution of the hull ribs, and the material is rubber or spring, which plays a damping and buffering role, and a rigid support is used near the stern, and free support is used in the other three circles. Under no-load conditions, the lower surface of the flexible outer plate of the bottom completely overlaps with the lower surface of the bottom plate. The device can isolate the impact acceleration from being directly transmitted to the boat, and improve the hydrodynamic performance of the planing boat by using the step-down effect generated by the passive deformation of the flexible structure.

Description

Technical Field

[0001] The invention belongs to the field of shock absorption and drag reduction of high-speed boats, and in particular relates to a local flexible bottom structure of a planing boat. Background Art

[0002] High-speed planing boats often run at high speeds on rough seas to intercept threats or respond to emergencies. When sailing at high speed in the sea, planing boats often partially or completely float out of the water and then enter the water at a high relative speed. The huge hydrodynamic load acts on the hull instantly, generating a violent vertical oscillation shock, and this impact load increases sharply with the increase in speed. The vibration of the human body and equipment on the boat caused by such impacts has been considered to be one of the main causes of health problems and equipment damage problems for planing boat crew members. In particular, the effects of frequent vibrations and repeated impacts on planing boat crew members include not only chronic and acute physical injuries but also psychological fatigue, which has seriously affected the comfort of drivers and passengers and may even cause injuries. Therefore, how to reduce the slamming vibration of planing boats is one of the key issues to improve the comprehensive performance of planing boats.

[0003] At present, the measures usually adopted to deal with the problem of severe slamming of planing boats are: 1) Strengthen the hull strength to avoid structural damage; 2) Optimize the ship type for wave resistance performance; 3) Add vibration reduction devices to protect personnel or equipment. But in fact, by strengthening the hull structure, the weight of the hull will be greatly increased, and it is impossible to slow down or even increase the acceleration of the slamming directly transmitted to the inside of the hull; and the change of the ship type usually means sacrificing other performance of the ship. For example, increasing the inclined rise angle will reduce the oscillation response of the planing boat in severe sea conditions, but the resistance will increase sharply. Adding vibration reduction devices is currently the most effective way to reduce shock, but the current vibration reduction devices usually cannot take into account the hydrodynamic performance of high-speed boats, or the device itself is complex, unreliable and costly.

[0004] Table 1 Comparison of existing vibration reduction measures for high-speed boats

[0005] Summary of the invention

[0006] The object of the present invention is to provide a local flexible bottom structure of a planing boat which has little influence on the overall performance of the boat and has a simple and reliable structure.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] A local flexible bottom structure of a planing boat comprises a flexible outer plate of the bottom, a flexible support and an inner bottom plate; the upper portion of the flexible outer plate of the bottom is glued to the flexible support, and a rigid connection is adopted between the stern and the hull, and the other three sides are free edges and are not connected; the flexible outer plate is distributed just below the rib plate of the planing boat and is connected to the inner bottom plate; the inner bottom plate and the bottom plate of the planing boat are a continuous structure.

[0009] The present invention may also include:

[0010] 1. The flexible outer plate of the ship bottom is composed of a composite material; the upper portion of the flexible outer plate of the ship bottom and the flexible support are bonded with high-strength glue.

[0011] 2. The flexible support is made of rubber or spring material; the flexible support and the inner bottom plate are connected by gluing or threading.

[0012] 3. After the local flexible bottom is installed, the lower surface of the flexible outer plate of the bottom of the ship completely overlaps with the lower surface of the bottom plate of the ship.

[0013] 4. When the bow of the planing boat is at the slamming position, the local flexible bottom structure is installed at 0.7 to 0.8 times the length of the boat; when the stern of the planing boat is at the slamming position, the local flexible bottom structure is installed at 0.2 to 0.3 times the length of the boat.

[0014] The beneficial effects of the present invention are:

[0015] The present invention can absorb and reduce the impact energy of the ship bottom by flexible deformation, and optimize the hydrodynamic performance of the planing boat by utilizing the step-down generated by the passive deformation of the flexible structure. At the same time, the structure does not require a large amount of layout space, has little impact on the overall performance of the ship, and has a simple and reliable structure.

[0016] The present invention slows down the transmission of impact acceleration to the inside of the hull without changing the hull weight or the hull type; the structure improves the hydrodynamic performance of the planing boat by utilizing the steps formed by the passive deformation of the local flexible bottom; the structure is simple in design, can be applied to a variety of high-speed boat types, and has good practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Top view of the local flexible bottom structure of the planing boat;

[0018] Figure 2 Longitudinal section of the local flexible bottom structure of the planing boat;

[0019] Figure 3 Longitudinal section view of the installation position of the local flexible bottom structure;

[0020] Figure 4 Schematic diagram of the flexible fracture deformation of the local flexible bottom structure of a planing craft under high-speed navigation. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with the accompanying drawings.

[0022] The present invention provides a local flexible bottom structure for a planing boat, which produces a step-down effect when the boat stern is deformed, and can be adjusted for different high-speed boats by changing the bottom structure. Figure 1 Middle angle α, spacing l nAnd flexible support materials are used to adjust the step-down effect, so as to improve the hydrodynamic performance of high-speed boats while absorbing energy and reducing vibration. Figure 1 and 2 As shown, it consists of three parts: the flexible outer plate 1 of the bottom, the flexible support 2, and the inner bottom plate 3. The flexible outer plate 1 of the bottom is made of composite materials. The upper part is bonded to the flexible support 2 with high-strength glue. The part near the stern is rigidly connected to the hull. The other three sides are free edges and are not connected. The length L in the figure is determined by the slamming range of the boat, usually 0.2 to 0.3 times the length of the boat. The width B is the same as the distance between the bilge fold line of the planing boat hull. The flexible support 2 is made of rubber or spring material. The flexible support 2 is distributed directly below the rib plate of the planing boat and is bonded or threaded to the inner bottom plate 3. The inclination angle of the flexible support α n and spacing l n Together control the deformation form of the flexible fracture bottom plate, when adjusting the support inclination angle α n When the flexible support is parallel to the pressure stagnation line at the bottom of the boat, the stepping effect of the flexible stepping is optimal. n The stationary point line acts on the flexible support, which can improve the shock absorption effect. The inner bottom plate 3 and the bottom plate of the planing boat are continuous structures.

[0023] like Figure 3 and 4 As shown in the figure, when sailing in different sea conditions, the slamming area is different. For example, the slamming of waves often comes from the bow repeatedly entering and exiting the water. The bow of the boat is used as the installation area of ​​the local flexible bottom, which is mainly used to absorb the hull vibration caused by wave slamming. According to the slamming position of the bow of the planing boat, the flexible step is installed at 0.7 to 0.8 times the ship length. In addition, the maximum speed of the planing boat is often limited by the dolphin motion caused by the coupling of pitch and heave. The slamming periodicity of the dolphin motion is obvious, and the pressure stagnation line is mostly concentrated near the stern. In view of the navigation characteristics of the high-speed planing boat, the 0.2 to 0.3 times the ship length is also used as the installation area of ​​the local flexible bottom.

[0024] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A local flexible bottom structure of a planing boat, characterized in that: The invention comprises a bottom flexible outer plate (1), a flexible support (2), and an inner bottom plate (3); the upper part of the bottom flexible outer plate (1) is glued to the flexible support (2), and a rigid connection is adopted between the hull and the stern side, and the other three sides are free sides and are not connected; the flexible support (2) is distributed directly below the rib plate of the planing boat and is connected to the inner bottom plate (3); the inner bottom plate (3) and the bottom plate of the planing boat are continuous structures; the bottom flexible outer plate (1) is composed of a composite material; the upper part of the bottom flexible outer plate (1) is glued to the flexible support (2), and a rigid connection is adopted between the stern side and the hull, and the other three sides are free sides and are not connected; the flexible support (2) is distributed directly below the rib plate of the planing boat and is connected to the inner bottom plate (3); the inner bottom plate (3) and the bottom plate of the planing boat are continuous structures; the bottom flexible outer plate (1) is composed of a composite material; the upper part of the bottom flexible outer plate (1) is glued to the flexible support ( 2) high-strength glue is used for bonding; the flexible support (2) is made of rubber or spring material; the flexible support (2) and the inner bottom plate (3) are connected by bonding or threading; after the local flexible bottom structure is installed, the lower surface of the flexible outer plate (1) of the bottom of the ship completely overlaps with the lower surface of the bottom plate; when the bow of the planing boat is at the slamming position, the local flexible bottom structure is installed at 0.7 to 0.8 times the length of the ship; when the stern of the planing boat is at the slamming position, the local flexible bottom structure is installed at 0.2 to 0.3 times the length of the ship.

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