A combined control method for bow and stern stabilizing fins of a small waterplane area catamaran

Abstract

The present invention relates to a combined control method for the bow and stern stabilizing fins of a small waterplane area catamaran (SWATH) vessel, comprising a SWATH vessel having symmetrically arranged bow fins mounted on the inner side of the bow portion and symmetrically arranged skeg fins mounted on the inner side of the stern portion. The SWATH vessel is equipped with a control system, an environmental perception sensor, and a hull attitude sensor. The combined control method for the bow and stern stabilizing fins comprises eight operating steps. By obtaining an engineering empirical formula relating hull resistance to the bow fin attack angle and the skeg fin attack angle, as well as the longitudinal stability equation of the SWATH vessel, the bow and stern fin adjustment angle values ​​are determined when the hull resistance is minimized, providing theoretical guidance for the stable navigation control of the SWATH vessel. By combined control of the bow and stern fins, the longitudinal stability requirements of the vessel can be met while ensuring the lowest hull resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of small waterplane area catamarans, in particular to a combined control method of bow and stern stabilizing fins of a small waterplane area catamaran. Background Art

[0002] Small waterplane area catamarans (SWATHs) are high-performance vessels consisting of deep-sea twin hulls, SWA struts, and a spacious upper hull. They offer excellent seakeeping and maneuverability, good directional stability, and a wide deck and upper deck with ample capacity. They are used in small and medium-sized passenger ships, ferries, and transportation vessels. Due to their unique line shape and configuration, the hydrodynamic effects of incoming water at varying speeds produce varying degrees of longitudinal capsizing moments on their submerged hulls under navigational conditions. This capsizing moment varies with speed, while the restoring moment is very small. Consequently, SWATHs exhibit poor longitudinal stability, resulting in significant pitch and roll during navigation.

[0003] Prior art uses a pair of stabilizing fins installed at the bow and stern of a SWATH vessel's submerged hull to mitigate pitch and roll. However, these fins are individually controlled and adjusted, lacking a mature, safe, and engineering-suitable method for combined control of the fins. This method, which can meet the requirements for longitudinal stability while minimizing hull resistance, is a key factor hindering the widespread adoption of SWATH vessels. Summary of the Invention

[0004] In response to the shortcomings in the above-mentioned existing production technology, the applicant provides a combined control method for the bow and stern stabilizing fins of a small waterplane area catamaran, obtains the engineering empirical formula between the hull resistance and the bow fin attack angle and the stern fin attack angle, as well as the longitudinal stability equation of the small waterplane area catamaran, thereby obtaining the bow fin and stern fin adjustment angle values ​​when the hull resistance is lowest, providing theoretical guidance for the stable navigation control of the small waterplane area catamaran, and by jointly controlling the bow and stern fins, it is possible to achieve the goal of ensuring the lowest hull resistance while meeting the longitudinal stability requirements of the ship.

[0005] The technical solutions adopted in the present invention are as follows:

[0006] A combined control method for bow and stern stabilizing fins of a small waterplane area catamaran comprises a small waterplane area catamaran, wherein the bow of the small waterplane area catamaran is equipped with symmetrically arranged bow fins on the inner side of the bow, and the stern of the small waterplane area catamaran is equipped with symmetrically arranged skeg fins on the inner side of the stern, and the small waterplane area catamaran is equipped with a control system, an environmental perception sensor, and a hull attitude sensor;

[0007] The combined control method of the bow and tail stabilizing fins includes the following steps:

[0008] S1. Establish a database of small waterplane area catamarans in the navigation state, including the structural parameters and size parameters of the hull, bow fin and tail fin of the small waterplane area catamaran;

[0009] S2. The speed of the small waterplane area catamaran is The hull resistance of the small waterplane area catamaran is obtained by the tank test method. Angle of attack with bow fin and the angle of attack of the tail fin The engineering experience formula between (Formula 1):

[0010] (Formula 1)

[0011] In (Formula 1), It represents the hull resistance of the small waterplane area catamaran; Indicates the speed of the small waterplane area catamaran; represents the angle of attack of the bow fin; represents the angle of attack of the tail fin; represents a constant, which is measured by fitting the pool test method;

[0012] S3. When the SWATH vessel is sailing, the velocity of the incoming flow is , then the resultant force of the incoming water dynamics acting on the bow fin (1) is It is obtained from the following formula:

[0013]

[0014] Where, It represents the resultant force of the incoming water dynamics acting on the bow fin. The angle with the horizontal direction is ;

[0015] Indicates the resistance of the first fin surface, which is the resultant force The component parallel to the incoming flow direction, ;

[0016] represents the lift on the first fin surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0017] Indicates the density of the incoming flow;

[0018] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, It represents the wake coefficient of the SWATH hull at the bow fin;

[0019] represents the total area of ​​the head fin;

[0020] It represents the drag coefficient of the incoming flow on the bow fin;

[0021] It represents the lift coefficient of the incoming flow on the bow fin;

[0022] Thus, the resultant force of the incoming water dynamics acting on the bow fin can be obtained Torque on the SWATH hull From the following formula we can get:

[0023]

[0024] Where, The resultant force of the incoming water on the bow fin Torque on the hull of a small waterplane area catamaran;

[0025] Represents the combined force vector of

[0026] The vector representing the distance from the floating center of the SWATH hull to the pressure center of the bow fin;

[0027] It represents the resultant force of the incoming water dynamics acting on the bow fin. The angle with the horizontal direction is ;

[0028] It represents the distance from the floating center of the SWATH hull to the pressure center of the bow fin. The angle between the line connecting the floating center of the SWATH hull to the pressure center of the bow fin and the horizontal direction is , , It indicates the angle between the line connecting the floating center of the SWATH hull to the pressure center of the bow fin and the horizontal line when the SWATH hull is in the initial state or horizontal state. Indicates the pitching cycle of the small waterplane area catamaran Pitch amplitude angle within ;

[0029] Represents a vector and The angle of , Represents the combined force The angle with the horizontal, It represents the angle between the line from the center of buoyancy of the SWATH hull to the pressure center of the bow fin and the horizontal direction;

[0030] Indicates the resistance of the first fin surface, which is the resultant force The component parallel to the incoming flow direction, ;

[0031] represents the lift on the first fin surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0032] Indicates the density of the incoming flow;

[0033] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, It represents the wake coefficient of the SWATH hull at the bow fin;

[0034] represents the total area of ​​the head fin;

[0035] It represents the drag coefficient of the incoming flow on the bow fin;

[0036] It represents the lift coefficient of the incoming flow on the bow fin;

[0037] S4. The resultant force of the incoming water on the tail fin It is obtained from the following formula:

[0038]

[0039] Where, It represents the resultant force of the incoming water dynamics acting on the tail fin. The angle with the horizontal direction is ;

[0040] Represents the tail fin surface resistance, which is the resultant force The component parallel to the incoming flow direction, ;

[0041] represents the lift on the tail fin surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0042] Indicates the density of the incoming flow;

[0043] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, It represents the wake coefficient of the SWATH hull at the skeg;

[0044] represents the total area of ​​the caudal fin;

[0045] It represents the drag coefficient of the incoming flow on the tail fin;

[0046] It represents the lift coefficient of the incoming flow on the tail fin;

[0047] Thus, the resultant force of the incoming water dynamics acting on the tail fin can be obtained Torque on the SWATH hull From the following formula we can get:

[0048]

[0049] Where, The resultant force of the incoming water on the tail fin Torque on the hull of a small waterplane area catamaran;

[0050] Represents the combined force vector of

[0051] The vector representing the distance from the floating center of the SWATH hull to the pressure center of the tail fin;

[0052] It represents the resultant force of the incoming water dynamics acting on the tail fin. The angle with the horizontal direction is ;

[0053] It represents the distance from the floating center of the SWATH hull to the pressure center of the tail fin. The angle between the line connecting the floating center of the SWATH hull to the pressure center of the tail fin and the horizontal direction is , , Indicates the angle between the line from the center of hull to the pressure center of the tail fin (2) and the horizontal line when the SWATH vessel is in the initial state or horizontal state. Indicates the pitching cycle of the small waterplane area catamaran Pitch amplitude angle within ;

[0054] Represents a vector and The angle of , Represents the combined force The angle with the horizontal, It represents the angle between the line from the center of buoyancy of the SWATH hull to the pressure center of the skeg and the horizontal direction;

[0055] Represents the tail fin surface resistance, which is the resultant force The component parallel to the incoming flow direction, ;

[0056] represents the lift on the tail fin surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0057] Indicates the density of the incoming flow;

[0058] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, It represents the wake coefficient of the SWATH hull at the skeg;

[0059] represents the total area of ​​the caudal fin;

[0060] It represents the drag coefficient of the incoming flow on the tail fin;

[0061] It represents the lift coefficient of the incoming flow on the tail fin;

[0062] S5. The bow fin and tail fin are located in front and behind the center of the SWATH hull, respectively. The torques generated by the combined force of the incoming water dynamics on the bow fin and tail fin are opposite. Then the sum of the torques on the bow and tail fins of the SWATH hull is ;

[0063] The resultant force of the incoming water dynamics acting on the bow fin obtained in step S3. Torque on the SWATH hull The resultant force of the incoming water dynamics on the tail fin obtained in step S4 is Torque on the SWATH hull The sum of the bow and tail fin torques of the small waterplane area catamaran can be obtained ;

[0064] S6. Obtain the sea conditions in which the SWATH vessel is sailing through the environmental perception sensors carried on the SWATH vessel, and obtain the longitudinal attitude of the SWATH vessel, i.e., the pitching period, through the hull attitude sensor. and a pitch cycle pitch angle ;

[0065] According to the basic principle of ships, for small tilt or rocking, to overcome the pitch angle Required torque ,

[0066] Where, Indicates the displacement of the small waterplane area catamaran;

[0067] It indicates that the ship has high longitudinal stability;

[0068] Thus, the longitudinal stability equation of the small waterplane area catamaran is obtained:

[0069] (Equation 2)

[0070] In (Equation 2), represents the sum of the bow and skeg torques of the small waterplane area catamaran obtained in step S5;

[0071] Indicates overcoming a pitch cycle pitch angle Required torque;

[0072] S7. According to the sea conditions and the speed of the SWATH , a pitch cycle pitch angle and pitch cycle , the hull resistance of the small waterplane area catamaran can be obtained from (Equation 1) and (Equation 2): Under the minimum condition, the attack angle of the bow fin is obtained and the angle of attack of the tail fin ;

[0073] At this time, the turning angle of the bow fin with reference to the SWATH hull is The turning angle of the tail fin with reference to the SWATH hull is , the rotation period of the bow and tail fins , represents the pitching period of the small waterplane area catamaran;

[0074] S8. During the voyage of the SWATH vessel, the vessel shall be , a pitch cycle pitch angle and pitch cycle The control system obtains the corresponding rotation period of the bow fin and tail fin according to step S7. The turning angle of the bow fin is based on the hull of the small waterplane area catamaran, and the turning angle of the tail fin is based on the hull of the small waterplane area catamaran. The turning angles of the bow fin and the tail fin are controlled to ensure the longitudinal stability of the small waterplane area catamaran and reduce the hull resistance of the small waterplane area catamaran. lowest.

[0075] As a further improvement of the above technical solution:

[0076] S2. The angle of attack of the bow fin Angle of attack with the tail fin Upward along the horizontal line is positive, downward is negative.

[0077] S3. 、 It can be obtained through the hydrodynamic characteristic curve of the incoming flow, and the angle of attack of the incoming flow Aspect ratio related;

[0078] In S4., 、 It can be obtained through the hydrodynamic characteristic curve of the incoming flow, and the angle of attack of the incoming flow Aspect ratio related.

[0079] In S6., the minimum inclination angle of the longitudinal rolling of the small waterplane area catamaran is less than 15°.

[0080] In S7., the rotation angles of the bow and tail fins must be within the mechanically adjustable range.

[0081] In S7., the navigation sea conditions of the small waterplane area catamaran are monitored in real time through the environmental perception sensor;

[0082] Real-time monitoring of a pitch cycle of the waterplane area catamaran through hull attitude sensors or gyroscopes pitch angle and pitch cycle .

[0083] In S8., when the pitching period of the SWATH hull is When , it means that the SWATH only has longitudinal inclination. At this time, the rotation period of the bow fin and tail fin is .

[0084] The angle of attack is positive upward along the horizontal line and negative downward along the horizontal line.

[0085] The beneficial effects of the present invention are as follows:

[0086] The present invention has reasonable steps and is easy to operate. By providing a method for jointly controlling and adjusting the turning angle values ​​of the bow fin and the tail fin, the influence of the attack angles of the bow and tail stabilizing fins on the hull resistance of the small waterplane area catamaran is fully considered, and when the resistance is minimized, the bow and tail fins can minimize the pitch and roll of the hull of the small waterplane area catamaran, thereby ensuring the operational stability of the ship.

[0087] The calculation method of the present invention is simple. The sea conditions in which the small waterplane area catamaran is sailing are obtained through environmental perception sensors, and the longitudinal attitude of the small waterplane area catamaran is obtained through hull attitude sensors. By substituting these into (Equation 1) and (Equation 2), the turning angle values ​​of the bow fin and the tail fin can be obtained. This solves the core technical problem of engineering applications in which the combined control of the bow and tail stabilizing fins satisfies the longitudinal stability requirements of the ship while minimizing the hull resistance.

[0088] In the present invention, a control system and corresponding sensor components are provided, and the sensor components can obtain the navigation conditions and longitudinal attitude of the small waterplane area catamaran in real time. The control system can promptly calculate the turning angle values ​​that need to be adjusted for the bow and tail fins based on the sea conditions and the attitude data of the ship, thereby ensuring that the small waterplane area catamaran always navigates in a stable condition with minimal resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0089] Figure 1 It is a rear view of the small waterplane area catamaran of the present invention.

[0090] Figure 2 It is a side view of the small waterplane area catamaran of the present invention (the right hull is omitted).

[0091] Figure 3 It is a side view of the small waterplane area catamaran in the present invention under sailing conditions (the right side is omitted).

[0092] Figure 4 It is a control flow chart of the present invention.

[0093] Among them: 1. Head fin; 2. Tail fin. DETAILED DESCRIPTION

[0094] The specific embodiments of the present invention will be described below with reference to the accompanying drawings.

[0095] Example 1:

[0096] like Figures 1-4 As shown, the combined control method of the bow and stern stabilizing fins of a small waterplane area catamaran of this embodiment includes a small waterplane area catamaran, wherein a bow fin 1 is symmetrically arranged on the inner side of the bow of the small waterplane area catamaran, and a skeg fin 2 is symmetrically arranged on the inner side of the stern of the small waterplane area catamaran. The small waterplane area catamaran is equipped with a control system, an environmental perception sensor, and a hull attitude sensor;

[0097] Figure 1-Figure 3In the figure, DWL represents the water level line and BL represents the datum line of the SWATH hull.

[0098] The small waterplane area catamaran consists of a double submerged hull, small waterplane area struts and a spacious upper hull. To improve its longitudinal stability during navigation, a pair of stabilizing fins, namely bow fin 1 and tail fin 2, are installed on the bow and stern hulls of the ship respectively.

[0099] The combined control method of the bow and tail stabilizing fins includes the following steps:

[0100] S1 establishes a database of small waterplane area catamarans in the navigation state, including the structural parameters and size parameters of the small waterplane area catamaran hull, the bow fin 1 and the tail fin 2;

[0101] S2. The speed of the small waterplane area catamaran is The hull resistance of the small waterplane area catamaran is obtained by the tank test method. Angle of attack with bow fin 1 and the angle of attack of tail fin 2 The engineering experience formula between (Formula 1):

[0102] (Formula 1)

[0103] In (Formula 1), It represents the hull resistance of the small waterplane area catamaran; Indicates the speed of the small waterplane area catamaran; represents the angle of attack of bow fin 1; represents the angle of attack of tail fin 2; represents a constant, which is measured by fitting the pool test method;

[0104] S2.1. Angle of attack of bow fin 1 Angle of attack with tail fin 2 Upward along the horizontal line is positive, downward is negative;

[0105] S2.2. Hull resistance of SWATH under certain sea conditions At ship speed When determining, (Equation 1) is a two-variable equation, and the angle of attack of the bow fin 1 and the angle of attack of tail fin 2 Related;

[0106] S3. When the SWATH vessel is sailing, the velocity of the incoming flow is , then the resultant force of the incoming water dynamics acting on the bow fin 1 is It is obtained from the following formula:

[0107]

[0108] Where, It represents the resultant force of the incoming water dynamics acting on the bow fin 1. The angle with the horizontal direction is ;

[0109] Indicates the resistance of the first fin 1 fin surface, which is the resultant force The component parallel to the incoming flow direction, ;

[0110] Indicates the lift on the first fin 1 surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0111] Indicates the density of the incoming flow;

[0112] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, represents the wake coefficient of the SWATH hull at the bow fin 1;

[0113] represents the total area of ​​the first fin 1;

[0114] represents the drag coefficient of the incoming flow on the bow fin 1;

[0115] represents the lift coefficient of the incoming flow on the bow fin 1;

[0116] Thus, the resultant force of the incoming water dynamics acting on the bow fin 1 can be obtained: Torque on the SWATH hull From the following formula we can get:

[0117]

[0118] Where, The resultant force of the incoming water dynamics acting on the bow fin 1 is Torque on the hull of a small waterplane area catamaran;

[0119] Represents the combined force vector of

[0120] The vector representing the distance from the floating center of the SWATH hull to the pressure center of the bow fin 1;

[0121] It represents the resultant force of the incoming water dynamics acting on the bow fin 1. The angle with the horizontal direction is ;

[0122] It represents the distance from the floating center of the SWATH hull to the pressure center of the bow fin 1. The angle between the line connecting the floating center of the SWATH hull to the pressure center of the bow fin 1 and the horizontal direction is , , It indicates the angle between the line connecting the center of hull buoyancy of the SWATH vessel and the pressure center of bow fin 1 and the horizontal line when the SWATH vessel is in the initial state or horizontal state. Indicates the pitching cycle of the small waterplane area catamaran Pitch amplitude angle within ;

[0123] Represents a vector and The angle of , Represents the combined force The angle with the horizontal, It represents the angle between the line from the center of buoyancy of the SWATH hull to the pressure center of the bow fin 1 and the horizontal direction;

[0124] Indicates the resistance of the first fin 1 fin surface, which is the resultant force The component parallel to the incoming flow direction, ;

[0125] Indicates the lift on the first fin 1 surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0126] Indicates the density of the incoming flow;

[0127] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, represents the wake coefficient of the SWATH hull at the bow fin 1;

[0128] represents the total area of ​​the first fin 1;

[0129] represents the drag coefficient of the incoming flow on the bow fin 1;

[0130] represents the lift coefficient of the incoming flow on the bow fin 1;

[0131] S3.1. 、 It can be obtained through the hydrodynamic characteristic curve of the incoming flow, and the angle of attack of the incoming flow Aspect ratio related;

[0132] S4. The resultant force of the incoming water dynamics acting on the tail fin 2 It is obtained from the following formula:

[0133]

[0134] Where, It represents the resultant force of the incoming water dynamics acting on the tail fin 2. The angle with the horizontal direction is ;

[0135] Indicates the resistance of the tail fin 2 surface, which is the resultant force The component parallel to the incoming flow direction, ;

[0136] Indicates the lift on the tail fin 2 surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0137] Indicates the density of the incoming flow;

[0138] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, represents the wake coefficient of the SWATH hull at the tail fin 2;

[0139] represents the total area of ​​tail fin 2;

[0140] represents the drag coefficient of the incoming flow on the tail fin 2;

[0141] represents the lift coefficient of the incoming flow on the tail fin 2;

[0142] Thus, the resultant force of the incoming water dynamics acting on the tail fin 2 can be obtained Torque on the SWATH hull From the following formula we can get:

[0143]

[0144] Where, The resultant force of the incoming water on the tail fin 2 is Torque on the hull of a small waterplane area catamaran;

[0145] Represents the combined force vector of

[0146] The vector representing the distance from the floating center of the SWATH hull to the pressure center of the tail fin 2;

[0147] It represents the resultant force of the incoming water dynamics acting on the tail fin 2. The angle with the horizontal direction is ;

[0148] It represents the distance from the floating center of the SWATH hull to the pressure center of the tail fin 2. The angle between the line connecting the floating center of the SWATH hull to the pressure center of the tail fin 2 and the horizontal direction is , , It represents the angle between the line connecting the center of hull drift to the pressure center of tail fin 2 and the horizontal line when the SWATH vessel is in the initial state or horizontal state. Indicates the pitching cycle of the small waterplane area catamaran Pitch amplitude angle within ;

[0149] Represents a vector and The angle of , Represents the combined force The angle with the horizontal, It represents the angle between the line from the center of buoyancy of the SWATH hull to the pressure center of the tail fin 2 and the horizontal direction;

[0150] Indicates the resistance of the tail fin 2 surface, which is the resultant force The component parallel to the incoming flow direction, ;

[0151] Indicates the lift on the tail fin 2 surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0152] Indicates the density of the incoming flow;

[0153] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, represents the wake coefficient of the SWATH hull at the tail fin 2;

[0154] represents the total area of ​​tail fin 2;

[0155] represents the drag coefficient of the incoming flow on the tail fin 2;

[0156] represents the lift coefficient of the incoming flow on the tail fin 2;

[0157] S4.1. 、 It can be obtained through the hydrodynamic characteristic curve of the incoming flow, and the angle of attack of the incoming flow Aspect ratio related;

[0158] S4.2. SWATH catamaran stern trim and pitch amplitude angle is positive;

[0159] S5. The bow fin 1 and the tail fin 2 are located in front and behind the center of the SWATH hull, respectively. The torques generated by the combined force of the incoming water power on the bow fin 1 and the tail fin 2 are opposite. Then the sum of the torques of the bow and tail fins of the SWATH hull is ;

[0160] The resultant force of the incoming water dynamics acting on the bow fin 1 obtained in step S3. Torque on the SWATH hull The resultant force of the incoming water dynamics on the tail fin 2 obtained in step S4. Torque on the SWATH hull The sum of the bow and tail fin torques of the small waterplane area catamaran can be obtained ;

[0161] S6. Obtain the sea conditions in which the SWATH vessel is sailing through the environmental perception sensors carried on the SWATH vessel, and obtain the longitudinal attitude of the SWATH vessel, i.e., the pitching period, through the hull attitude sensor. and a pitch cycle pitch angle ;

[0162] According to the basic principle of ships, for small tilt or rocking, to overcome the pitch angle Required torque ,

[0163] Where, Indicates the displacement of the small waterplane area catamaran;

[0164] It indicates that the ship has high longitudinal stability;

[0165] Thus, the longitudinal stability equation of the small waterplane area catamaran is obtained:

[0166] (Equation 2)

[0167] In (Equation 2), represents the sum of the bow and skeg torques of the small waterplane area catamaran obtained in step S5;

[0168] Indicates overcoming a pitch cycle pitch angle Required torque;

[0169] S6.1. Small inclination angle less than 15°;

[0170] S7. According to the sea conditions and the speed of the SWATH , a pitch cycle pitch angle and pitch cycle , the hull resistance of the small waterplane area catamaran can be obtained from (Equation 1) and (Equation 2): Under the minimum condition, the attack angle of the bow fin 1 is obtained and the angle of attack of tail fin 2 ;

[0171] At this time, the turning angle of the bow fin 1 with the SWATH hull as reference is The turning angle of tail fin 2 with reference to the SWATH hull is , the rotation period of the bow fin 1 and the tail fin 2 , represents the pitching period of the small waterplane area catamaran;

[0172] S7.1. The rotation angles of the bow fin 1 and the tail fin 2 must be within the mechanically adjustable range.

[0173] S7.2. Use environmental sensing sensors to monitor the sea conditions of the SWATH vessel in real time, and use hull attitude sensors or gyroscopes to monitor the pitching cycle of the SWATH vessel in real time. pitch angle and pitch cycle ;

[0174] S8. During the voyage of the SWATH vessel, the vessel shall be , a pitch cycle pitch angle and pitch cycle The control system obtains the corresponding rotation period of the bow fin 1 and the tail fin 2 according to step S7. The turning angle of the bow fin 1 and the tail fin 2 is based on the small waterplane area catamaran hull, and the turning angle of the bow fin 1 and the tail fin 2 is based on the small waterplane area catamaran hull. The turning angles of the bow fin 1 and the tail fin 2 are controlled to ensure the longitudinal stability of the small waterplane area catamaran and reduce the resistance of the small waterplane area catamaran hull. lowest;

[0175] S8.1. When the pitching period of the SWATH hull When , it means that the SWATH only has trim and no longitudinal rolling. At this time, the rotation period of bow fin 1 and tail fin 2 is The bow fin 1 and the tail fin 2 do not swing periodically and are only used to improve the longitudinal inclination of the small waterplane area catamaran.

[0176] This embodiment provides a combined control method for the bow and stern stabilizing fins of a small waterplane area catamaran, which can improve the longitudinal stability of the ship, reduce the ship's pitch and pitch, and fully consider the effect of the stabilizing fin attack angle on the hull resistance of the small waterplane area catamaran. The influence of the bow and tail stabilizer fins is solved by combining the control to meet the longitudinal stability requirements of the ship and reduce the hull resistance of the small waterplane area catamaran. The lowest engineering application problem improves the operational stability of the small waterplane area catamaran.

[0177] Example 2:

[0178] like Figure 2-Figure 4 As shown, this embodiment provides a combined control method for the bow and stern stabilizer fins of a small waterplane area catamaran according to the first embodiment, and takes a 100-ton small waterplane area catamaran as an example to illustrate the specific implementation steps;

[0179] The total length of the small waterplane area catamaran is about 30m, the width is about 12m, and the speed is The range is 0-10.3m / s;

[0180] The density of seawater When sailing in sea areas, a pair of stabilizing fins, namely bow fins 1, are installed at the bow of the ship, and a pair of stabilizing fins, namely tail fins 2, are installed at the stern of the ship;

[0181] The steps are as follows:

[0182] S1 establishes a database of small waterplane area catamarans in the navigation state, including the structural parameters and size parameters of the small waterplane area catamaran hull, the bow fin 1 and the tail fin 2;

[0183] S1.1. Distance from the center of buoyancy of the SWATH hull to the center of pressure of the bow fin 1 In the initial state, the angle between the line connecting the floating center of the small waterplane area catamaran to the pressure center of the bow fin 1 and the horizontal line is ;

[0184] The distance from the floating center of the small waterplane area catamaran hull to the pressure center of the tail fin 2 In the initial state, the angle between the line connecting the floating center of the SWATH hull to the pressure center of the tail fin 2 and the horizontal line is ;

[0185] S2. The speed of the small waterplane area catamaran is The hull resistance of the small waterplane area catamaran is obtained by the tank test method. Angle of attack with bow fin 1 and the angle of attack of tail fin 2 The engineering experience formula between (Formula 1):

[0186] (Formula 1)

[0187] In (Formula 1), It represents the hull resistance of the small waterplane area catamaran; Indicates the speed of the small waterplane area catamaran; represents the angle of attack of bow fin 1; represents the angle of attack of tail fin 2; represents a constant, which is measured by fitting the pool test method;

[0188] S2.1. The constants in Equation 1 are obtained from the tank test method, and are vertically converted to:

[0189] (Formula 1)

[0190] S2.2. Angle of attack of bow fin 1 Angle of attack with tail fin 2 Upward along the horizontal line is positive, downward is negative;

[0191] S2.3. Hull resistance of SWATH under certain sea conditions At ship speed When determining, (Equation 1) is a two-variable equation, and the angle of attack of the bow fin 1 and the angle of attack of tail fin 2 Related;

[0192] S3. When the SWATH vessel is sailing, the velocity of the incoming flow is , then the resultant force of the incoming water dynamics acting on the bow fin 1 is It is obtained from the following formula:

[0193]

[0194] Where, It represents the resultant force of the incoming water dynamics acting on the bow fin 1. The angle with the horizontal direction is ;

[0195] Indicates the resistance of the first fin 1 fin surface, which is the resultant force The component parallel to the incoming flow direction, ;

[0196] Indicates the lift on the first fin 1 surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0197] Indicates the density of the incoming flow;

[0198] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, It represents the wake coefficient of the small waterplane area twin-hull ship at the bow fin 1. In this embodiment, Take 0.1;

[0199] Indicates the total area of ​​the first fin 1. In this embodiment ;

[0200] The drag coefficient of the incoming flow on the bow fin 1 is obtained from the hydrodynamic characteristic curve of the fin surface of the bow fin 1 in this embodiment. ;

[0201] represents the lift coefficient of the incoming flow on the bow fin 1, which is obtained from the hydrodynamic characteristic curve of the tail fin 2 in this embodiment. ;

[0202] Thus, the resultant force of the incoming water dynamics acting on the bow fin 1 can be obtained: Torque on the SWATH hull From the following formula we can get:

[0203]

[0204] Where, The resultant force of the incoming water dynamics acting on the bow fin 1 is Torque on the hull of a small waterplane area catamaran;

[0205] Represents the combined force vector of

[0206] The vector representing the distance from the floating center of the SWATH hull to the pressure center of the bow fin 1;

[0207] It represents the resultant force of the incoming water dynamics acting on the bow fin 1. The angle with the horizontal direction is ;

[0208] It represents the distance from the floating center of the SWATH hull to the pressure center of the bow fin 1. The angle between the line connecting the floating center of the SWATH hull to the pressure center of the bow fin 1 and the horizontal direction is , In this embodiment , For a small waterplane area catamaran in a pitching cycle Pitch amplitude angle within ;

[0209] Represents a vector and The angle of , Represents the combined force The angle with the horizontal, It represents the angle between the line from the center of buoyancy of the SWATH hull to the pressure center of the bow fin 1 and the horizontal direction;

[0210] Indicates the resistance of the first fin 1 fin surface, which is the resultant force The component parallel to the incoming flow direction, ;

[0211] Indicates the lift on the first fin 1 surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0212] Indicates the density of the incoming flow;

[0213] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, It represents the wake coefficient of the small waterplane area twin-hull ship at the bow fin 1. In this embodiment, Take 0.1;

[0214] Indicates the total area of ​​the first fin 1. In this embodiment ;

[0215] The drag coefficient of the incoming flow on the bow fin 1 is obtained from the hydrodynamic characteristic curve of the fin surface of the bow fin 1 in this embodiment. ;

[0216] represents the lift coefficient of the incoming flow on the bow fin 1, which is obtained from the hydrodynamic characteristic curve of the tail fin 2 in this embodiment. ;

[0217] In this embodiment, the resultant force of the incoming water power acting on the bow fin 1 is Torque on the SWATH hull :

[0218]

[0219] S3.1. 、 It can be obtained through the hydrodynamic characteristic curve of the incoming flow, and the angle of attack of the incoming flow Aspect ratio related;

[0220] S3.2. SWATH catamaran stern trim and pitch amplitude angle is positive;

[0221] S4. The resultant force of the incoming water dynamics acting on the tail fin 2 It is obtained from the following formula:

[0222]

[0223] Where, It represents the resultant force of the incoming water dynamics acting on the tail fin 2. The angle with the horizontal direction is ;

[0224] Indicates the resistance of the tail fin 2 surface, which is the resultant force The component parallel to the incoming flow direction, ;

[0225] Indicates the lift on the tail fin 2 surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0226] Indicates the density of the incoming flow;

[0227] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, It represents the wake coefficient of the small waterplane area twin-hull ship at the tail fin 2. In this embodiment, Take 0.1;

[0228] Indicates the total area of ​​the tail fin 2. In this embodiment ;

[0229] The drag coefficient of the incoming flow on the tail fin 2 is obtained from the hydrodynamic characteristic curve of the tail fin 2 in this embodiment. ;

[0230] represents the lift coefficient of the incoming flow on the tail fin 2, which is obtained from the hydrodynamic characteristic curve of the tail fin 2 in this embodiment. ;

[0231] Thus, the resultant force of the incoming water dynamics acting on the tail fin 2 can be obtained Torque on the SWATH hull From the following formula we can get:

[0232]

[0233] Where, The resultant force of the incoming water on the tail fin 2 is Torque on the hull of a small waterplane area catamaran;

[0234] Represents the combined force vector of

[0235] The vector representing the distance from the floating center of the SWATH hull to the pressure center of the tail fin 2;

[0236] It represents the resultant force of the incoming water dynamics acting on the tail fin 2. The angle with the horizontal direction is ;

[0237] It represents the distance from the floating center of the SWATH hull to the pressure center of the tail fin 2. The angle between the line connecting the floating center of the SWATH hull to the pressure center of the tail fin 2 and the horizontal direction is , In this embodiment , For a small waterplane area catamaran in a pitching cycle Pitch amplitude angle within ;

[0238] Represents a vector and The angle of , Represents the combined force The angle with the horizontal, It represents the angle between the line from the center of buoyancy of the SWATH hull to the pressure center of the tail fin 2 and the horizontal direction;

[0239] Indicates the resistance of the tail fin 2 surface, which is the resultant force The component parallel to the incoming flow direction, ;

[0240] Indicates the lift on the tail fin 2 surface, which is the resultant force The component perpendicular to the incoming flow direction, ;

[0241] Indicates the density of the incoming flow;

[0242] Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, It represents the wake coefficient of the small waterplane area twin-hull ship at the tail fin 2. In this embodiment, Take 0.1;

[0243] Indicates the total area of ​​the tail fin 2. In this embodiment ;

[0244] The drag coefficient of the incoming flow on the tail fin 2 is obtained from the hydrodynamic characteristic curve of the tail fin 2 in this embodiment. ;

[0245] represents the lift coefficient of the incoming flow on the tail fin 2, which is obtained from the hydrodynamic characteristic curve of the tail fin 2 in this embodiment. ;

[0246] In this embodiment, the resultant force of the incoming water power acting on the tail fin 2 is Torque on the SWATH hull :

[0247]

[0248] S4.1. 、 It can be obtained through the hydrodynamic characteristic curve of the incoming flow, and the angle of attack of the incoming flow Aspect ratio related;

[0249] S4.2. SWATH catamaran stern trim and pitch amplitude angle is positive;

[0250] S5. The bow fin 1 and the tail fin 2 are located in front and behind the center of the SWATH hull, respectively. The torques generated by the combined force of the incoming water power on the bow fin 1 and the tail fin 2 are opposite. Then the sum of the torques of the bow and tail fins of the SWATH hull is ;

[0251] The resultant force of the incoming water dynamics acting on the bow fin 1 obtained in step S3. Torque on the SWATH hull The resultant force of the incoming water dynamics on the tail fin 2 obtained in step S4. Torque on the SWATH hull The sum of the bow and tail fin torques of the small waterplane area catamaran can be obtained ;

[0252] S6. Obtain the sea conditions in which the SWATH vessel is sailing through the environmental perception sensors carried on the SWATH vessel, and obtain the longitudinal attitude of the SWATH vessel, i.e., the pitching period, through the hull attitude sensor. and a pitch cycle pitch angle In this embodiment ;

[0253] According to the basic principle of ships, for small tilt or rocking, to overcome the pitch angle Required torque ,

[0254] Where, Indicates the displacement of the small waterplane area catamaran. In this embodiment ;

[0255] Indicates that the longitudinal stability of the ship is high. ;

[0256] Thus, the longitudinal stability equation of the small waterplane area catamaran is obtained:

[0257] (Equation 2)

[0258] In (Equation 2), represents the sum of the bow and skeg torques of the small waterplane area catamaran obtained in step S5;

[0259] Indicates overcoming a pitch cycle pitch angle Required torque;

[0260] In this embodiment, to overcome the pitch angle Required torque :

[0261]

[0262] You can get: ;

[0263] S6.1. Small inclination angle less than 15°;

[0264] S7. According to the sea conditions and the speed of the SWATH , a pitch cycle pitch angle and pitch cycle , the hull resistance of the small waterplane area catamaran can be obtained from (Equation 1) and (Equation 2): Under the minimum condition, the attack angle of the bow fin 1 is obtained and the angle of attack of tail fin 2 ;

[0265] At this time, the turning angle of the bow fin 1 with reference to the SWATH hull is The turning angle of tail fin 2 with reference to the SWATH hull is , the rotation period of the bow fin 1 and the tail fin 2 , represents the pitching period of the small waterplane area catamaran;

[0266] In this embodiment, the speed of the small waterplane area catamaran is , a pitching cycle of the small waterplane area catamaran Pitch amplitude angle At this time, the angle between the line connecting the floating center of the small waterplane area catamaran hull to the pressure center of the bow fin 1 and the horizontal direction is The angle between the line connecting the center of hull of SWATH and the pressure center of tail fin 2 and the horizontal direction is ;

[0267] According to (Equation 1) and (Equation 2), within the mechanically adjustable range of the rotation angles of the bow fin 1 and the tail fin 2, the hull resistance of the small waterplane area catamaran is Under the minimum condition, the attack angle of the bow fin 1 is obtained , and the angle of attack of tail fin 2 ,

[0268] At this time, the turning angle of the bow fin 1 with reference to the SWATH hull is The turning angle of tail fin 2 with reference to the SWATH hull is ;

[0269] In this embodiment, the mechanically adjustable range of the rotation angles of the bow fin 1 and the tail fin 2 is: ;

[0270] S7.2. Use environmental sensing sensors to monitor the sea conditions of the SWATH vessel in real time, and use hull attitude sensors or gyroscopes to monitor the pitching cycle of the SWATH vessel in real time. pitch angle and pitch cycle ;

[0271] S8. During the voyage of the SWATH vessel, the vessel shall be , a pitch cycle pitch angle and pitch cycle The control system obtains the corresponding rotation period of the bow fin 1 and the tail fin 2 according to step S7. The turning angle of the bow fin 1 and the tail fin 2 is based on the small waterplane area catamaran hull, and the turning angle of the bow fin 1 and the tail fin 2 is based on the small waterplane area catamaran hull. The turning angles of the bow fin 1 and the tail fin 2 are controlled to ensure the longitudinal stability of the small waterplane area catamaran and reduce the resistance of the small waterplane area catamaran hull. lowest;

[0272] S8.1. When the pitching period of the SWATH hull When , it means that the SWATH only has trim and no longitudinal rolling. At this time, the rotation period of bow fin 1 and tail fin 2 is The bow fin 1 and the tail fin 2 do not swing periodically and are only used to improve the longitudinal inclination of the small waterplane area catamaran.

[0273] This embodiment takes a 100-ton small waterplane area catamaran as an example and provides the specific operating steps of a combined control method for the bow and stern stabilizer fins of a small waterplane area catamaran in Example 1. This control method can ensure the longitudinal stability of the small waterplane area catamaran, reduce the impact of pitch and tilt on the stability of the ship, and at the same time ensure the hull resistance at this time. The lowest is the theoretically optimal control mode.

[0274] The above description is an explanation of the present invention, not a limitation of the present invention. The scope of the present invention is defined in the claims. Any modifications may be made within the scope of protection of the present invention.

Claims

1. A combined control method for bow and stern stabilizer fins of a small waterplane area catamaran, characterized by: The invention comprises a small waterplane area catamaran, wherein the inner side of the bow of the small waterplane area catamaran is equipped with a symmetrically arranged bow fin (1), the inner side of the stern of the small waterplane area catamaran is equipped with a symmetrically arranged tail fin (2), and the small waterplane area catamaran is equipped with a control system, an environmental perception sensor and a hull attitude sensor; The combined control method of the bow and tail stabilizing fins includes the following steps: S1. Establishing a database of a small waterplane area catamaran in a sailing state, the database includes structural parameters and size parameters of the hull, bow fin (1) and tail fin (2) of the small waterplane area catamaran; S2. The speed of the small waterplane area catamaran is The hull resistance of the small waterplane area catamaran is obtained by the tank test method. Angle of attack with respect to the bow fin (1) and the angle of attack of the tail fin (2) The engineering experience formula between (Formula 1): (Formula 1) In (Formula 1), It represents the hull resistance of the small waterplane area catamaran; Indicates the speed of the small waterplane area catamaran; represents the angle of attack of the bow fin (1); represents the angle of attack of the tail fin (2); represents a constant, which is measured by fitting the pool test method; S3. When the SWATH vessel is sailing, the velocity of the incoming flow is , then the resultant force of the incoming water dynamics acting on the bow fin (1) is It is obtained from the following formula: Where, The resultant force of the incoming water dynamics acting on the bow fin (1) is The angle with the horizontal is ; represents the resistance of the first fin (1) and is the resultant force The component parallel to the incoming flow direction, ; represents the lift force on the fin surface of the first fin (1), which is the resultant force The component perpendicular to the incoming flow direction, ; Indicates the density of the incoming flow; Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, represents the wake coefficient of the SWATH hull at the bow fin (1); represents the total area of ​​the head fin (1); represents the drag coefficient of the incoming flow on the bow fin (1); represents the lift coefficient of the incoming flow on the bow fin (1); Thus, the resultant force of the incoming water dynamics acting on the bow fin (1) can be obtained: Torque on the SWATH hull From the following formula we can get: Where, The resultant force of the incoming water on the bow fin (1) is Torque on the hull of a small waterplane area catamaran; Represents the combined force vector of The vector representing the distance from the floating center of the SWATH hull to the pressure center of the bow fin (1); The resultant force of the incoming water dynamics acting on the bow fin (1) is The angle with the horizontal is ; It represents the distance from the floating center of the SWATH hull to the pressure center of the bow fin (1). The angle between the line connecting the floating center of the SWATH hull to the pressure center of the bow fin (1) and the horizontal direction is , , It represents the angle between the line from the center of hull to the pressure center of the bow fin (1) and the horizontal line when the SWATH vessel is in the initial state or horizontal state. Indicates the pitching cycle of the small waterplane area catamaran Pitch amplitude angle within ; Represents a vector and The angle of , Represents the combined force The angle with the horizontal, The angle between the line from the center of buoyancy of the SWATH hull to the center of pressure of the bow fin (1) and the horizontal direction; represents the resistance of the first fin (1) and is the resultant force The component parallel to the incoming flow direction, ; represents the lift force on the fin surface of the first fin (1), which is the resultant force The component perpendicular to the incoming flow direction, ; Indicates the density of the incoming flow; Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, represents the wake coefficient of the SWATH hull at the bow fin (1); represents the total area of ​​the head fin (1); represents the drag coefficient of the incoming flow on the bow fin (1); represents the lift coefficient of the incoming flow on the bow fin (1); S4. The resultant force of the incoming water dynamics acting on the tail fin (2) It is obtained from the following formula: Where, The resultant force of the incoming water dynamics acting on the tail fin (2) is represented by The angle with the horizontal is ; represents the tail fin (2) fin surface resistance, which is the resultant force The component parallel to the incoming flow direction, ; represents the lift force on the tail fin (2), which is the resultant force The component perpendicular to the incoming flow direction, ; Indicates the density of the incoming flow; Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, represents the wake coefficient of the SWATH hull at the skeg (2); represents the total area of ​​the caudal fin (2); represents the drag coefficient of the incoming flow on the tail fin (2); represents the lift coefficient of the incoming flow on the tail fin (2); Thus, the resultant force of the incoming water dynamics acting on the tail fin (2) can be obtained: Torque on the SWATH hull From the following formula we can get: Where, The resultant force of the incoming water on the tail fin (2) is Torque on the hull of a small waterplane area catamaran; Represents the combined force vector of The vector representing the distance from the floating center of the SWATH hull to the pressure center of the tail fin (2); The resultant force of the incoming water dynamics acting on the tail fin (2) is represented by The angle with the horizontal is ; It represents the distance from the floating center of the SWATH hull to the pressure center of the tail fin (2). The angle between the line connecting the floating center of the SWATH hull to the pressure center of the tail fin (2) and the horizontal direction is , , Indicates the angle between the line from the center of hull to the pressure center of the tail fin (2) and the horizontal line when the SWATH vessel is in the initial state or horizontal state. Indicates the pitching cycle of the small waterplane area catamaran Pitch amplitude angle within ; Represents a vector and The angle of , Represents the combined force The angle with the horizontal, The angle between the line from the center of hull drift of the SWATH vessel to the center of pressure of the tail fin (2) and the horizontal direction; represents the tail fin (2) fin surface resistance, which is the resultant force The component parallel to the incoming flow direction, ; represents the lift force on the tail fin (2), which is the resultant force The component perpendicular to the incoming flow direction, ; Indicates the density of the incoming flow; Indicates the flow rate of the incoming flow, , where Indicates the speed of the small waterplane area catamaran, represents the wake coefficient of the SWATH hull at the skeg (2); represents the total area of ​​the caudal fin (2); represents the drag coefficient of the incoming flow on the tail fin (2); represents the lift coefficient of the incoming flow on the tail fin (2); S5. The bow fin (1) and the tail fin (2) are located in front and behind the center of the hull of the small waterplane area catamaran. The torques generated by the combined force of the incoming water power on the bow fin (1) and the tail fin (2) are opposite. Then the sum of the torques of the bow and tail fins of the small waterplane area catamaran is ; The resultant force of the incoming water dynamics acting on the bow fin (1) obtained in step S3. Torque on the SWATH hull The resultant force of the incoming water dynamics on the tail fin (2) obtained in step S4 is Torque on the SWATH hull The sum of the bow and tail fin torques of the small waterplane area catamaran can be obtained ; S6. Obtain the sea conditions in which the SWATH vessel is sailing through the environmental perception sensors carried on the SWATH vessel, and obtain the longitudinal attitude of the SWATH vessel, i.e., the pitching period, through the hull attitude sensor. and a pitch cycle pitch angle ; According to the basic principle of ships, for small tilt or rocking, to overcome the pitch angle Required torque , Where, Indicates the displacement of the small waterplane area catamaran; It indicates that the ship has high longitudinal stability; Thus, the longitudinal stability equation of the small waterplane area catamaran is obtained: (Equation 2) In (Equation 2), represents the sum of the bow and skeg torques of the small waterplane area catamaran obtained in step S5; Indicates overcoming a pitch cycle pitch angle Required torque; S7. According to the sea conditions and the speed of the SWATH , a pitch cycle pitch angle and pitch cycle , the hull resistance of the small waterplane area catamaran can be obtained from (Equation 1) and (Equation 2): Under the minimum condition, the attack angle of the bow fin (1) is obtained and the angle of attack of the tail fin (2) ; At this time, the turning angle of the bow fin (1) with reference to the SWATH hull is The turning angle of the tail fin (2) with reference to the SWATH hull is , the rotation period of the bow fin (1) and the tail fin (2) , represents the pitching period of the small waterplane area catamaran; S8. During the voyage of the SWATH vessel, the vessel shall be , a pitch cycle pitch angle and pitch cycle , the control system obtains the corresponding rotation period of the bow fin (1) and the tail fin (2) according to step S7. The turning angle of the bow fin (1) is based on the hull of the small waterplane area catamaran, and the turning angle of the tail fin (2) is based on the hull of the small waterplane area catamaran. The turning angles of the bow fin (1) and the tail fin (2) are controlled to ensure the longitudinal stability of the small waterplane area catamaran and reduce the hull resistance of the small waterplane area catamaran. lowest.

2. The combined control method for bow and stern stabilizer fins of a small waterplane area catamaran according to claim 1, characterized in that: In S2., the angle of attack of the bow fin (1) Angle of attack with the tail fin (2) Upward along the horizontal line is positive, downward along the horizontal line is negative.

3. The combined control method for bow and stern stabilizer fins of a small waterplane area catamaran according to claim 1, characterized in that: S3. 、 It can be obtained through the hydrodynamic characteristic curve of the incoming flow, and the angle of attack of the incoming flow Aspect ratio related; In S4., 、 It can be obtained through the hydrodynamic characteristic curve of the incoming flow, and the angle of attack of the incoming flow Aspect ratio related.

4. The combined control method for bow and stern stabilizer fins of a small waterplane area catamaran according to claim 1, characterized in that: In S6., the minimum inclination angle of the longitudinal rolling of the small waterplane area catamaran is less than 15°.

5. The combined control method for bow and stern stabilizer fins of a small waterplane area catamaran according to claim 1, characterized in that: In S7., the rotation angles of the bow fin (1) and the tail fin (2) must be within the mechanically adjustable range.

6. The combined control method for bow and stern stabilizer fins of a small waterplane area catamaran according to claim 1, characterized in that: In S7., the navigation sea conditions of the small waterplane area catamaran are monitored in real time through the environmental perception sensor; Real-time monitoring of a pitch cycle of the waterplane area catamaran through hull attitude sensors or gyroscopes pitch angle and pitch cycle .

7. The combined control method for bow and stern stabilizer fins of a small waterplane area catamaran according to claim 1, characterized in that: In S8., when the pitching period of the SWATH hull is When , it means that the SWATH only has longitudinal inclination. At this time, the rotation period of the bow fin (1) and the tail fin (2) is .

8. The combined control method for bow and stern stabilizer fins of a small waterplane area catamaran according to claim 1, characterized in that: The angle of attack is positive upward along the horizontal line and negative downward along the horizontal line.

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