CN115356081A - A small waterplane area catamaran towing test device and test method - Google Patents

Abstract

The application provides a towing test device and a towing test method for a catamaran with a small waterplane area. The test device comprises a small waterplane area catamaran model, a towing device and a measuring assembly. The upper ends of the first sheet body structure and the second sheet body structure of the model are fixedly connected with the right side and the left side of the fixed frame beam respectively and are inclined by a preset angle. The second and first sheet structures are symmetrical about the central longitudinal section. The power device of the towing device is used for moving along a parallel water surface track, the towing structure is rotationally connected with the first sheet structure and the second sheet structure, the connection position of the towing structure and the first sheet structure is a first towing point and a second towing point, the first towing point and the second towing point are respectively the intersection point of the cross section where the center of gravity of the ship model is located and the two thrust axes, and the connecting line of the towing points is the model pitching rotation axis. The towing structure is vertically connected with the power device in a sliding manner. The transverse-moving and transverse-inclining preventing structure is used for limiting transverse-inclining rotation of the model. The measuring assembly measures a pitch angle, a heave amount and a drag force. The method and the device realize the geometric similarity of a drag force action point and a real ship thrust action point, and ensure the longitudinal motion freedom of the heave and pitch of the model.

Description

A small waterplane area catamaran towing test device and test method

technical field

The application relates to the technical field of small waterplane area catamaran model tank testing, in particular to a small waterplane area catamaran towing test device and test method.

Background technique

The small waterplane area catamaran is a high-performance ship type evolved by integrating the advantages of various ship types in actual marine activities such as developing marine resources and defending maritime rights and interests. A conventional small waterplane area catamaran consists of an upper hull and two upright pieces fixed below the upper hull. In addition, the oblique strut small waterplane area catamaran has gradually been developed and applied. This ship type has a smaller superstructure and a longer hull structure. When carrying out related model tests, more ship type elements (such as The distance between the hulls and the angle of inclination of the hulls) need to be considered, which makes the model test of the inclined strut SWAPA catamaran more complicated technically.

Different from conventional monohulls and catamarans, small waterplane area catamarans have small longitudinal static restoring moments due to their smaller waterplane area, which are often not enough to balance the water acting on the hull during high-speed navigation. The dynamic trim moment and other disturbance forces, the longitudinal motion attitude is more obviously affected by the trim moment, the longitudinal motion stability has become an important difficulty in the performance design of small waterplane area catamarans, and model tests are needed to study it .

In the conventional method, when carrying out the test of the small waterplane area catamaran model, it is necessary to use an external power device to push the small waterplane area catamaran model to sail in the test pool, and the different pushing positions will bring different effects to the model. The trim moment of the model will change the longitudinal motion attitude of the model, and even lead to severe trim at high speeds, which will have a great impact on the test results and cannot accurately predict the longitudinal motion performance of the real ship.

In addition, since the size of the small waterplane area catamaran model is much smaller than the actual ship size, the model test will also produce a relatively obvious heel, but the conventional test does not consider the effect of eliminating the heel on the trim, so As a result, the longitudinal motion data of the model obtained through the test is inaccurate, and the longitudinal motion performance of the real ship cannot be accurately predicted.

Contents of the invention

The purpose of the embodiment of the present application is to provide a small waterplane area catamaran towing test device, which can realize the geometric similarity between the model drag force action point and the real ship thrust action point in vertical height, and at the same time ensure the vertical height of the model. The degree of freedom of longitudinal motion of sway and pitch improves the accuracy of the small waterplane area catamaran towing test and provides technical support for its hydrodynamic performance research.

The second purpose of the embodiments of the present application is also to provide a method for performing a small waterplane area catamaran towing test using the above-mentioned small waterplane area catamaran towing test device.

In the first aspect, a small waterplane area catamaran towing test device is provided, including a small waterplane area catamaran model, a towing device and a measurement component. Wherein, the small waterplane area catamaran model includes a fixed frame girder, a first sheet structure and a second sheet structure. The upper end of the first sheet structure is fixedly connected to the right side of the fixed frame beam, so that the first sheet structure is inclined at a predetermined angle. The upper end of the second sheet structure is fixedly connected to the left side of the fixed frame beam, so that the second sheet structure is inclined at a predetermined angle, and the second sheet structure and the first sheet structure are arranged symmetrically with respect to the longitudinal section of the middle position of the fixed frame beam. The towing device includes a power unit, a towing structure and an anti-sway and roll structure. The power device is erected above the test pool and is used to move at a predetermined speed along a predetermined track parallel to the water surface. The drag structure is rotatably connected to the first sheet structure and the second sheet structure respectively, the connection between the drag structure and the first sheet structure is the first drag point, and the connection between the drag structure and the second sheet structure is the second drag point. Two tow points, the first tow point and the second tow point are the intersection points of the cross-section where the center of gravity of the small waterplane catamaran model is located and the two thrust axes; the line connecting the first tow point and the second tow point is the small waterline The axis of the trim and rotation of the surface catamaran model; the dragging structure is slidingly connected with the power unit, and the sliding direction is always the vertical direction. The anti-sway and heel structure is used to keep the longitudinal axis of the small waterplane catamaran model consistent with the forward direction of the power plant, and to limit the heeling rotation of the small waterplane catamaran model. The measurement component is used to measure the trim angle and heave of the small waterplane area catamaran model and the towing force of the towing device.

In an implementable solution, the first sheet structure includes a first submerged body in which the first support plate is fixedly connected to the lower end of the first support plate, and the upper end of the first sheet structure is fixedly connected to the right side of the fixed frame beam, so that the first A plate is inclined at a predetermined angle; the second sheet structure includes a second support plate and a second submerged body fixed to the lower end of the second support plate, and the upper end of the second sheet structure is fixedly connected to the left side of the fixed frame beam, so that the second support plate The plate is inclined at a predetermined angle, and the second sheet structure and the first sheet structure are arranged symmetrically with respect to the longitudinal section at the middle position of the fixed frame beam; The connection between the towing structure and the second submerged body is the first towing point, and the connection between the towing structure and the second submerged body is the second towed point. A towing point, the intersection of the axis of the second submersible and the cross-section where the center of gravity of the small waterplane catamaran model is located is the second towing point.

In an implementable solution, a plurality of installation positions distributed along the lateral direction of the body are provided on the fixed frame beam, and the installation positions of the first sheet structure and the second sheet structure on the fixed frame beam are adjusted to adjust the installation positions of the first sheet structure and the second sheet structure. The spacing between one sheet structure and the second sheet structure.

In an implementable solution, a first cavity is provided in the first support plate, and the inside of the first submerged body is a cavity, and the first cavity extends from the upper end of the first support plate to the lower end and communicates with the first submerged body An internal cavity; a second cavity is arranged in the second support plate, and the inside of the second submerged body is a cavity, and the second cavity extends from the upper end of the second support plate to the lower end and communicates with the cavity inside the second submerged body; The towing structure comprises a first pull rod, a second pull rod, a fixed plate and a vertical rod, the two ends of the fixed plate are respectively connected to the upper ends of the first pull rod and the second pull rod, and the vertical rod is installed on the fixed plate and connected to the The power unit is slidably connected in the vertical direction; the lower end of the first drag rod passes through the first cavity of the first support plate, and extends into the first submerged body to connect to the position of the first tow point, the inclination of the first drag rod The angle is consistent with the inclination angle of the first support plate; the lower end of the second drag rod passes through the second cavity of the second support plate, and extends into the second submerged body to connect to the position of the first tow point, the second drag rod The angle of inclination is consistent with the angle of inclination of the second support plate.

In a practicable solution, the first sheet structure includes a reinforcement frame, the reinforcement frame includes a rib plate and a support frame, the support frame is arranged in the first submerged body and is fixedly connected with the first submerged body, and the rib plate is arranged in the first submerged body. The lower end of the rib plate is fixedly connected with the support frame, the upper end of the rib plate is fixedly connected with the fixed frame beam, the first drag point is located on the support frame, the lower end of the first drag rod is rotatably connected with the support frame, and the rotation axis is connected with the second The axis of a submerged body is vertical and parallel to the fixed frame beam; the structure of the second sheet structure is the same as that of the first sheet structure.

In an implementable solution, in the first sheet structure, the support frame of the reinforcement frame includes vertical plates at both ends, a connecting rod and a support platform arranged between the two vertical plates, and the two vertical plates are connected to the first The inner wall of the submerged body cavity is connected, the connecting rod is parallel to the axis of the first submerged body, the supporting platform is slidably and fixedly installed on the connecting rod, the lower end of the first drag rod is rotatably connected with the supporting platform, and the rotating axis is connected with the second The axis of a submerged body is vertical and parallel to the fixed frame beam; the structure of the second sheet structure is the same as that of the first sheet structure.

In an implementable solution, in the first sheet structure, the first submerged body is provided with a through threaded hole. After the support platform is adjusted along the connecting rod, a screw is used to fit the threaded hole and tighten it. The supporting platform; the structure of the second sheet structure is the same as that of the first sheet structure.

In a practicable solution, the measurement assembly includes a drag force measurement device, and the drag force measurement device includes a support body, a vertical sleeve, a tension pressure sensor, shrapnel, a pneumatic clamp, a slider and a slide bar; the top of the support body and the The power unit is fixedly connected; the pneumatic clamp and the sliding rod are fixed on the support body, and the sliding rod is consistent with the longitudinal direction of the small waterplane catamaran model; the sliding block is slidably socketed on the sliding rod, and the two ends of the sliding rod are respectively fixed A shrapnel is set to prevent the slider from slipping out of the slider; one end of the tension pressure sensor is connected to the slider, and the other end is connected to the slider. The tension and pressure direction of the tension pressure sensor is consistent with the longitudinal direction of the small waterplane catamaran model. Used to measure the drag force of the dragging device; the vertical sleeve is fixed at one end of the slider, and the vertical rod is inserted into the vertical sleeve to form a sliding fit; when the pneumatic clamp is opened, the slider can slide along the slide rod; when the pneumatic clamp is closed, it clamps Slider so that the slider cannot slide along the slider.

In a practicable solution, the drag force measuring device further includes a laser displacement sensor, which is installed on the support body, facing the upper end surface of the vertical rod, and is separated by a predetermined distance.

In a practicable solution, the measurement component includes an inclination sensor, which is arranged on the fixed frame girder and is used for measuring the trim angle of the small waterplane area catamaran model.

In a practical solution, the anti-swaying and tilting structure includes a rectangular frame and a guide rod; the rectangular frame is fixedly connected to the fixed frame beam, and a rectangular hole extending longitudinally is arranged on the rectangular frame, and the longitudinal centerline of the rectangular hole In the longitudinal section at the middle position of the fixed frame beam, the upper end of the guide rod is fixedly connected with the power device, and the lower end of the guide rod is inserted into the rectangular hole of the rectangular frame.

According to the second aspect of the present application, there is also provided a small waterplane area catamaran towing test method, using the small waterplane area catamaran towing test device in the above scheme, the test method includes the following steps:

According to the actual size of the small waterplane area catamaran, the size of each component of the small waterplane area catamaran model is determined according to the predetermined scale ratio, and the spacing and The actual inclination angle is fixedly connected with the fixed frame beam, and other components are assembled in sequence according to the connection relationship;

According to the actual draft and floating state of the small waterplane area catamaran, determine and adjust the draft and floating state of the small waterplane area catamaran model according to the predetermined scale ratio;

确定小水线面双体船模型的拖曳速度V_m，其中λ为缩尺比，V_s为实际小水线面双体船的航速，航速V_s在预定范围内按预定间隔选取若干速度点，对应得到若干拖曳速度V_m；according to the formula

Determine the towing speed V _m of the small waterplane area catamaran model, where λ is the scale ratio, V _s is the actual speed of the small waterplane area catamaran, and the speed V _s is within the predetermined range and selected several speed points at predetermined intervals , corresponding to several drag velocities V _m ;

Several towing speeds V _m are tested in turn, and the power device is started to tow the SWS catamaran model in the test pool according to the predetermined trajectory. When the SWS catamaran model accelerates to the set towing speed, at least Collect the towing force and the trim angle and heave of the small waterplane catamaran model, complete a towing speed test, and repeat the above steps until the test of all towing speed points is completed;

After the test is completed, analyze the collected data.

Compared with the prior art, the beneficial effects of the present application are: in the technical scheme of the present application, the small waterplane area catamaran model is formed by using the fixed frame girder, the first sheet structure and the second sheet structure, and the actual A scaled model of a small waterplane area catamaran. The towing structure is connected downwards with the intersection of the center of gravity of the small waterplane catamaran model and the intersection of the two thrust axes. On the one hand, the first towing point and the second towing point are formed, and the line connecting the two It constitutes the rotation axis of the small waterplane catamaran model, ensuring that the model has the degree of freedom of pitching. On the other hand, it transmits the drag force to the thrust axis and the transverse section of the center of gravity of the small waterplane catamaran model At the intersection point of the ship, the simulation of the thrust point of the ship is realized as realistic as possible, so that the trim of the small waterplane catamaran model can simulate the trim of the real ship, effectively eliminating the severe and Trim beyond the normal range, so that the model can truly predict the longitudinal motion performance of the real ship.

Furthermore, the dragging structure is slidingly connected to the power unit upwards, and the entire dragging device can only move up and down along the position of the sliding connection, which ensures that the model has a degree of freedom of heaving. On the one hand, the drag force generated by the movement of the power unit can be transmitted to the position of the drag point through the drag structure. On the other hand, since the small waterplane area catamaran model will generate vertical heave when navigating in the water, the sliding connection between the towing structure and the power device can well undertake the vertical heave of the ship model .

In addition, the solution of this embodiment restricts the rolling of the SWAPS catamaran model by means of the anti-sway and heel structure, so that the model basically does not generate unnecessary heel, so as to eliminate the effect of heel on the accuracy of longitudinal motion data. Impact.

To sum up, the small waterplane area catamaran towing test device in this embodiment realizes the geometric similarity between the model drag force action point and the actual ship thrust action point in vertical height, and ensures the heave and pitch of the model at the same time. The degree of freedom of longitudinal movement improves the accuracy of the small waterplane area catamaran towing test and provides technical support for its hydrodynamic performance research.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the accompanying drawings used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, so It should be regarded as a limitation on the scope, and those skilled in the art can also obtain other related drawings based on these drawings without creative work.

Fig. 1 is a schematic diagram of the overall structure of a small waterplane area catamaran towing test device shown according to an embodiment of the present application;

Fig. 2 is a schematic structural diagram of a small waterplane area catamaran model and a towing structure according to an embodiment of the present application;

Fig. 3 is a structural schematic diagram of a small waterplane area catamaran model along a longitudinal perspective according to an embodiment of the present application;

Fig. 4 is a front structural schematic view of a drag force measuring device shown according to an embodiment of the present application;

Fig. 5 is a schematic perspective view of a drag force measuring device according to an embodiment of the present application.

In the figure: 10, small waterplane area catamaran model; 11, fixed frame beam; 111, installation position; 12, the first sheet structure; 121, the first support plate; 122, the first submerged body; 123, the first A cavity; 13, the second sheet structure; 131, the second support plate; 132, the second submerged body; 133, the second cavity; 14, the reinforcement frame; 141, the rib plate; 142, the support frame; 1421 Riser; 1422, connecting rod; 1423, support platform; 20, towing device; 21, power unit; 211, trailer measuring bridge; 22, towing structure; 221, first tow bar; 222, second tow bar; 223, Fixed plate; 224, vertical rod; 23, anti-sway and tilt structure; 231, rectangular frame; 232, guide rod; 30, drag force measuring device; 31, support body; 32, vertical sleeve; 33, pull Pressure sensor; 34, shrapnel; 35, pneumatic clamp; 36, slider; 37, slide bar; 38, optical displacement sensor; 40, inclination sensor.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of this application, not all of them. The components of the embodiments of the application generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations.

Accordingly, the following detailed description of the embodiments of the application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the application. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of this application.

What needs to be explained first is that, referring to Figures 1, 2 and 3, the direction of the coordinate x-axis is horizontal, and the direction of the coordinate y-axis is longitudinal. is a plane parallel to the plane where xoz is located.

According to the first aspect of the present application, as shown in Figures 1-3, a small waterplane area catamaran towing test device is firstly provided, including a small waterplane area catamaran model, a towing device and a measurement component.

Wherein, the small waterplane area catamaran model includes a fixed frame girder 11 , a first sheet structure 12 and a second sheet structure 13 . The upper end of the first sheet structure 12 is fixedly connected to the right side of the fixed frame beam 11, so that the first sheet structure 12 is inclined at a predetermined angle. The upper end of the second sheet structure 13 is fixedly connected to the left side of the fixed frame beam 11, so that the second sheet structure 13 is inclined at a predetermined angle, and the second sheet structure 13 and the first sheet structure 12 are vertically aligned with the middle position of the fixed frame beam 11. The section is symmetrically arranged. The towing device includes a power unit 21 , a towing structure 22 and an anti-sway and roll structure 23 . The power device 21 is erected above the test pool, and is used to move at a predetermined speed along a predetermined trajectory parallel to the water surface. The dragging structure 22 is rotatably connected with the first sheet structure 12 and the second sheet structure 13 respectively, and the joint between the dragging structure 22 and the first sheet structure 12 is the first dragging point, and the dragging structure 22 and the second sheet structure The junction of 13 is the second tow point, the first tow point and the second tow point are respectively the cross section where the center of gravity of the small waterplane catamaran model is located and the intersection of the two thrust axes; the first tow point and the second tow point The connecting line is the axis of trim rotation of the small waterplane area catamaran model; the dragging structure 22 is slidingly connected with the power unit 21, and the sliding direction is always the vertical direction. The anti-traversing and heeling structure 23 is used to keep the longitudinal axis of the small waterplane catamaran model consistent with the forward direction of the power unit 21, and to limit the heeling rotation of the small waterplane catamaran model. The measurement component is used to measure the trim angle and heave of the small waterplane area catamaran model and the towing force of the towing device.

In the technical solution of the above-mentioned embodiment, the small waterplane area catamaran model is formed by using the fixed frame beam 11, the first sheet structure 12 and the second sheet structure 13, and the actual scale of the small waterplane area catamaran is obtained. Model. The towing structure 22 is connected downwards with the cross section where the center of gravity of the small waterplane catamaran model is located and the intersection of the two thrust axes. On the one hand, it forms the first towing point and the second towing point. The line constitutes the rotation axis of the small waterplane catamaran model, ensuring that the model has the degree of freedom of pitching. On the other hand, the drag force is transmitted to the thrust axis and the center of gravity of the small waterplane catamaran model. At the intersection of the sections, the simulation of the thrust point of the ship is realized as realistic as possible, so that the trim of the small waterplane catamaran model can simulate the trim of the real ship, and effectively eliminates the seriousness of the model caused by the unreasonable position of the propulsion. And the trim exceeds the normal range, so that the model can truly predict the longitudinal motion performance of the real ship.

Furthermore, the dragging structure 22 is upwardly slidably connected with the power device 21, and the entire dragging structure 22 can only move up and down along the position of the sliding connection, which ensures that the model has a degree of freedom of heaving. On the one hand, the dragging force generated by the movement of the power device 21 can be transmitted to the position of the dragging point through the dragging structure 22 . On the other hand, since the small waterplane area catamaran model will generate vertical heave when navigating in water, the sliding connection between the dragging structure 22 and the power unit 21 can well undertake the vertical heave of the ship model. weight.

In addition, the solution of this embodiment restricts the rolling of the small waterplane area catamaran model by means of the anti-swaying and heeling structure 23, so that the model basically does not generate unnecessary heeling, so as to eliminate the effect of heeling on the accuracy of longitudinal motion data. Impact.

To sum up, the small waterplane area catamaran towing test device in this embodiment realizes the geometric similarity between the model drag force action point and the actual ship thrust action point in vertical height, and ensures the heave and pitch of the model at the same time. The degree of freedom of longitudinal movement enables the small waterplane area catamaran model to pitch and heave within a certain range, while limiting the lateral displacement and inclination, which improves the accuracy of the small waterplane area catamaran towing test. The data of trim angle, heave, and drag force of the small waterplane area catamaran model test are further obtained by means of measurement components, so as to provide technical support for its hydrodynamic performance research.

It should be noted that, as shown in Figure 1, the power unit 21 of the towing device can include a trailer bridge 211, a track and a drive assembly, and a track for the movement of the trailer bridge 211 is set up on the test pool, and then the trailer bridge 211 Installed on the track, the trailer measuring bridge 211 is driven to move along the track through the drive assembly, thereby driving the towing structure 22 to move.

In one embodiment, as shown in FIGS. 1-3 , the first sheet structure 12 includes a first submerged body 122 in which the first support plate 121 is fixedly connected to the lower end of the first support plate 121 , and the upper end of the first sheet structure 12 is It is fixedly connected with the right side of the fixed frame beam 11, so that the first support plate 121 is inclined at a predetermined angle. The second sheet structure 13 includes a second support plate 131 and a second submerged body 132 fixedly connected to the lower end of the second support plate 131, and the upper end of the second sheet structure 13 is fixedly connected to the left side of the fixed frame beam 11, so that the second support plate 131 is inclined at a predetermined angle, and the second sheet structure 13 and the first sheet structure 12 are arranged symmetrically with respect to the longitudinal section at the middle position of the fixed frame beam 11 . The drag structure 22 is rotatably connected with the first submerged body 122 and the second submerged body 132, the connection between the drag structure 22 and the first submerged body 122 is the first tow point, and the connection between the tow structure 22 and the second submerged body 132 is The second towing point, the intersection of the axis of the first submerged body 122 and the cross-section where the center of gravity of the small waterplane catamaran model is the first towing point, the axis of the second submersible 132 and the small waterplane catamaran model The intersection point of the cross section where the center of gravity is located is the second drag point.

For the small waterplane area catamaran's sheet structure is in the form of inclination, the first support plate 121 and the second support plate 131 can be installed to adjust to the same inclination angle as the real ship, thereby simulating small water with different inclination angles. Line surface catamaran. At the same time, by changing the installation positions of the first support plate 121 and the second support plate 131 on the fixed frame beam 11, the adjustment of the spacing between the sheet structures can be realized, so as to better simulate different types of small waterplane area catamarans .

In a specific embodiment, as shown in Fig. 3, a plurality of mounting positions 111 distributed along the lateral direction of the main body are arranged on the fixed frame beam 11, and the first sheet structure 12 and the second sheet structure 13 are adjusted in the fixed position. The installation position 111 on the frame beam 11 is used to adjust the distance between the first sheet structure 12 and the second sheet structure 13 to realize the adjustment of the distance between the sheet structures to better simulate different types of small waterlines face catamaran.

In one embodiment, as shown in FIG. 1 , a first cavity 123 is provided in the first support plate 121 , the interior of the first submersible body 122 is a cavity, and the first cavity 123 extends from the upper end of the first support plate 121 to the lower end and communicate with the cavity inside the first submerged body 122 . A second cavity 133 is arranged in the second support plate 131, and the inside of the second submerged body 132 is a cavity. The second cavity 133 extends from the upper end of the second support plate 131 to the lower end and communicates with the cavity inside the second submerged body 132. . Further, the towing structure 22 includes a first tow bar 221, a second tow bar 222, a fixed plate 223 and a vertical bar 224, and the two ends of the fixed plate 223 are respectively connected to the upper ends of the first tow bar 221 and the second tow bar 222 , the vertical rod 224 is installed on the fixed plate 223 and is slidably connected with the power device 21 along the vertical direction. The lower end of the first drag rod 221 passes through the first cavity 123 of the first support plate 121, and extends into the first submerged body 122 to be connected to the position of the first tow point. The inclination angle of the first drag rod 221 is the same as the first The inclination angles of the support plates 121 are consistent. The lower end of the second drag rod 222 passes through the second cavity 133 of the second support plate 131, and stretches into the second submerged body 132 to be connected to the position of the first drag point. The inclination angle of the second drag rod 222 is the same as that of the second The inclination angles of the support plates 131 are consistent.

In the above-mentioned embodiment, the first dragging rod 221 and the second dragging rod 222 of the dragging structure 22 are hidden in the first cavity 123 and the second cavity 133 respectively, thereby isolating the contact of the dragging structure 22 with the water flow and reducing non-small The water flow disturbance caused by the body structure of the water plane catamaran model is used to reduce the influence of irrelevant variables on the accuracy of the test.

In one embodiment, as shown in FIG. 2, the first sheet structure 12 includes a reinforcement frame 14, and the reinforcement frame 14 includes a rib plate 141 and a support frame 142, and the support frame 142 is arranged in the first submerged body 122 and is connected to the first submerged body 122. A submerged body 122 is fixedly connected, the rib plate 141 is arranged in the first support plate 121, and the lower end of the rib plate 141 is fixedly connected with the support frame 142, and the upper end of the rib plate 141 is fixedly connected with the fixed frame beam 11, and the first drag point is located at the support frame 142, the lower end of the first drag rod 221 is rotatably connected to the support frame 142, and the rotation axis is perpendicular to the axis of the first submerged body 122 and parallel to the fixed frame beam 11; the second sheet structure 13 and the first sheet structure 12 The structure is the same. The reinforcing frame 14 is conducive to strengthening the strength and stability of the sheet structure.

In one embodiment, as shown in FIG. 2, in the first sheet structure 12, the supporting frame 142 of the reinforcement frame 14 includes vertical plates 1421 at both ends, connecting rods 1422 and Support platform 1423, two vertical plates 1421 are connected with the inner wall of the cavity of the first submerged body 122, the connecting rod 1422 is parallel to the axis of the first submerged body 122, and the supporting platform 1423 is slidably and fixedly installed on the connecting rod 1422, The lower end of the first drag rod 221 is rotatably connected to the support platform 1423, and the rotation axis is perpendicular to the axis of the first submersible 122 and parallel to the fixed frame beam 11; the second sheet structure 13 has the same structure as the first sheet structure 12. When the towing point is not at the intersection of the cross section where the center of gravity of the small waterplane catamaran model is located and the thrust axis, or there is an installation error, or the position changes after multiple tests, then the support platform 1423 can be adjusted on the connecting rod 1422 The upper position is equivalent to adjusting the position of the towing point along the thrust axis, so that the towing point is located in the cross-section of the center of gravity of the SWS catamaran model as much as possible.

In one embodiment, in the first sheet structure 12, the first submerged body 122 is provided with a through screw hole (not shown in the figure), after the support platform 1423 is adjusted along the connecting rod 1422, use A screw (not shown in the figure) cooperates with the threaded hole and presses against the supporting platform 1423; the second sheet structure 13 has the same structure as the first sheet structure 12. The above results in a structure for adjusting the position of the support platform 1423 on the connecting rod 1422 .

In one embodiment, as shown in Figures 4 and 5, the measurement assembly includes a drag force measurement device 30, which includes a support body 31, a vertical sleeve 32, a tension pressure sensor 33, a shrapnel 34, a pneumatic clamp 35, slide block 36 and slide bar 37. The top of the supporting body 31 is fixedly connected with the power device 21 . The pneumatic clamp 35 and the slide bar 37 are fixed on the support body 31, and the slide bar 37 is consistent with the longitudinal direction of the small waterplane area catamaran model. The sliding block 36 is slidably socketed on the sliding rod 37 , and an elastic piece 34 is fixedly arranged at each end of the sliding rod 37 to prevent the sliding block 36 from sliding out of the sliding rod 37 . One end of the pull-pressure sensor 33 is connected with the slide bar 37, and the other end is connected with the slide block 36. The pull-pressure direction of the pull-pressure sensor 33 is consistent with the longitudinal direction of the small waterplane area catamaran model, which is convenient for measuring the dragging force of the towing device. The vertical sleeve 32 is fixed on one end of the slider 36, and the vertical rod 224 is inserted into the vertical sleeve 32 to form a sliding fit. When the pneumatic clamp 35 is opened, the slide block 36 can slide along the slide bar 37;

In one embodiment, as shown in Figures 4 and 5, the drag force measuring device 30 also includes a laser displacement sensor 38, which is installed on the support body 31, facing the upper end surface of the vertical rod 224, and is separated by a predetermined distance , used to measure the heave of the small waterplane area catamaran model. Other distance measuring structures or other distance measuring sensors can also be used to measure the heave.

In one embodiment, as shown in FIGS. 1 and 2 , the measurement assembly includes an inclination sensor 40 , which is arranged on the fixed frame girder 11 for measuring the trim angle of the small waterplane area catamaran model.

In an implementation of the anti-sway and heel structure 23, the sliding fit structure of the drag structure 22 and the power unit 21 in the vertical direction can be used as the anti-sway and heel structure 23, which can only be restricted by sliding in the numerical direction. Roll and roll. Specifically, the vertical rod 224 can be set as a direction, and the vertical sleeve 32 is a square hole, and the cooperation of the two can not only limit sliding up and down, but also prevent rotation, so as to limit the occurrence of lateral movement and tilting of the model.

In a preferred embodiment of the anti-sway and roll structure 23 , as shown in FIG. 1 , the anti-sway and roll structure 23 includes a rectangular frame 231 and a guide rod 232 . The rectangular frame 231 is fixedly connected with the fixed frame beam 11, and the rectangular frame 231 is provided with a rectangular hole extending longitudinally, and the longitudinal center line of the rectangular hole is in the longitudinal section of the middle position of the fixed frame beam 11, and the upper end of the guide rod 232 is connected to the power unit. 21 is fixedly connected, and the lower end of the guide rod 232 is inserted into the rectangular hole of the rectangular frame 231. The cooperation between the guide rod 232 and the rectangular frame 231 prevents the lateral movement and lateral inclination of the model during the drag test on the one hand, and on the other hand does not restrict the model. vertical inclination.

According to the second aspect of the present application, there is also provided a small waterplane area catamaran towing test method, using the small waterplane area catamaran towing test device in the above scheme, the test method includes the following steps:

S1. According to the actual size of the small waterplane catamaran, determine the size of each component of the small waterplane catamaran model according to the predetermined scale ratio, and scale the first sheet structure 12 and the second sheet structure 13 according to the same proportion The final spacing and actual inclination angle are fixedly connected with the fixed frame beam 11, and other components are assembled in sequence according to the connection relationship;

S2. According to the actual draft and floating state of the small waterplane area catamaran, determine and adjust the draft and floating state of the small waterplane area catamaran model according to the predetermined scale ratio;

确定小水线面双体船模型的拖曳速度V_m，其中λ为缩尺比，V_s为实际小水线面双体船的航速，航速V_s在预定范围内按预定间隔选取若干速度点，对应得到若干拖曳速度V_m；S3, according to the formula

Determine the towing speed V _m of the small waterplane area catamaran model, where λ is the scale ratio, V _s is the actual speed of the small waterplane area catamaran, and the speed V _s is within the predetermined range and selected several speed points at predetermined intervals , corresponding to several drag velocities V _m ;

S4. Test a number of towing speeds V _m in turn, start the power unit 21 to tow the small waterplane area catamaran model in the test pool according to the predetermined trajectory, and wait for the small waterplane area catamaran model to accelerate to the set towing speed , at least collect the towing force and the trim angle and heave of the small waterplane area catamaran model, complete a towing speed test, and repeat the above steps until the test of all towing speed points is completed;

S5. After the test is completed, analyze the collected data.

In step S2, the draft and floating state of the SWS catamaran model can be adjusted by increasing or decreasing the counterweight in the fixed frame girder 11 and/or the first submerged body 122 and the second submerged body 132 .

In the above test, the pool water temperature, water density, model weight, center of gravity position, wet surface area, initial pitch angle, test speed, drag resistance, etc. can also be collected, and combined with the drag force, heave and pitch angle, the force of the test model can be obtained. , heave and trim angle with the speed of the ship, in order to analyze the longitudinal movement of the model.

The above are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, there may be various modifications and changes in the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included within the protection scope of this application.

Claims (12)

1. The small waterplane area catamaran towing test device is characterized by comprising a small waterplane area catamaran model, a towing device and a measuring assembly:

the small waterplane area catamaran model comprises:

a fixed frame beam (11);

the upper end of the first sheet structure (12) is fixedly connected with the right side of the fixed frame beam (11), so that the first sheet structure (12) is inclined at a preset angle;

the upper end of the second sheet structure (13) is fixedly connected with the left side of the fixed frame beam (11) so that the second sheet structure (13) is inclined by a preset angle, and the second sheet structure (13) and the first sheet structure (12) are symmetrically arranged relative to the longitudinal section of the middle position of the fixed frame beam (11);

the towing device includes:

the power device (21) is erected above the test water pool and is used for moving at a preset speed along a preset track parallel to the water surface;

a towing structure (22) rotatably connected to the first sheet structure (12) and the second sheet structure (13), respectively, wherein a joint of the towing structure (22) and the first sheet structure (12) is a first towing point, a joint of the towing structure (22) and the second sheet structure (13) is a second towing point, and the first towing point and the second towing point are intersection points of a cross section where the gravity center of the small waterplane catamaran model is located and two thrust axes, respectively; the connecting line of the first towing point and the second towing point is the trim rotation axis of the small waterplane area catamaran model; the dragging structure (22) is connected with the power device (21) in a sliding mode, and the sliding direction is always the vertical direction;

a transverse and transverse inclination preventing structure (23) which is used for enabling the longitudinal axis of the small waterplane area catamaran model to be consistent with the advancing direction of a power device (21) all the time and limiting the small waterplane area catamaran model to generate transverse inclination rotation;

the measuring assembly is used for measuring the pitch angle, the heave capacity and the drag force of the towing device of the small waterplane area catamaran model.

2. The small waterplane area catamaran towing test apparatus according to claim 1,

the first sheet structure (12) comprises a first support plate (121) and a first submerged body (122) fixedly connected with the lower end of the first support plate (121), and the upper end of the first sheet structure (12) is fixedly connected with the right side of the fixed frame beam (11) to enable the first support plate (121) to incline by a preset angle;

the second sheet structure (13) comprises a second support plate (131) and a second latent body (132) fixedly connected with the lower end of the second support plate (131), the upper end of the second sheet structure (13) is fixedly connected with the left side of the fixed frame beam (11) so that the second support plate (131) is inclined by a preset angle, and the second sheet structure (13) and the first sheet structure (12) are symmetrically arranged about the longitudinal section of the middle position of the fixed frame beam (11);

the towing structure (22) is rotatably connected with the first submerged body (122) and the second submerged body (132), the joint of the towing structure (22) and the first submerged body (122) is a first towing point, the joint of the towing structure (22) and the second submerged body (132) is a second towing point, the intersection point of the axis of the first submerged body (122) and the cross section of the small waterplane catamaran model gravity center is the first towing point, and the intersection point of the axis of the second submerged body (132) and the cross section of the small waterplane catamaran model gravity center is the second towing point.

3. The small waterplane area catamaran towing test apparatus according to claim 1, wherein a plurality of mounting positions (111) are provided on the fixed frame beam (11) in a lateral direction along a body thereof, and the mounting positions (111) of the first blade structure (12) and the second blade structure (13) on the fixed frame beam (11) are adjusted to adjust a distance between the first blade structure (12) and the second blade structure (13).

4. The small waterplane area catamaran drag test apparatus according to claim 2, wherein a first cavity (123) is provided in the first strut (121), the first submerged body (122) is internally provided with a cavity, and the first cavity (123) extends from the upper end to the lower end of the first strut (121) and is communicated to the cavity inside the first submerged body (122);

a second cavity (133) is arranged in the second support plate (131), the interior of the second submerged body (132) is a cavity, and the second cavity (133) extends from the upper end to the lower end of the second support plate (131) and is communicated with the cavity in the second submerged body (132);

the towing structure (22) comprises a first towing rod (221), a second towing rod (222), a fixing plate (223) and a vertical rod (224), two ends of the fixing plate (223) are respectively connected with the upper ends of the first towing rod (221) and the second towing rod (222), and the vertical rod (224) is installed on the fixing plate (223) and is connected with the power device (21) in a slidable mode along the vertical direction;

the lower end of the first drag rod (221) penetrates through the first cavity (123) of the first supporting plate (121) and extends into the first submerged body (122) to be connected to the first drag point, and the inclination angle of the first drag rod (221) is consistent with that of the first supporting plate (121);

the lower end of the second drag rod (222) penetrates through the second cavity (133) of the second support plate (131) and extends into the second submerged body (132) to be connected to the first drag point, and the inclination angle of the second drag rod (222) is consistent with that of the second support plate (131).

5. The small waterplane area catamaran towing test apparatus according to claim 4, wherein the first sheet structure (12) comprises a reinforcing frame (14), the reinforcing frame (14) comprises rib plates (141) and a supporting frame (142), the supporting frame (142) is arranged in the first submerged body (122) and fixedly connected with the first submerged body (122), the rib plates (141) are arranged in the first support plate (121), the lower ends of the rib plates (141) are fixedly connected with the supporting frame (142), the upper ends of the rib plates (141) are fixedly connected with the fixed frame beam (11), the first towing point is located on the supporting frame (142), the lower ends of the first towing rods (221) are rotatably connected with the supporting frame (142), and the rotation axis is perpendicular to the axis of the first submerged body (122) and parallel to the fixed frame beam (11);

the second sheet structure (13) is identical in structure to the first sheet structure (12).

6. The small waterplane area catamaran towing test apparatus according to claim 5, wherein in the first sheet structure (12), the supporting frame (142) of the reinforcing frame (14) comprises vertical plates (1421) at two ends, a connecting rod (1422) and a supporting platform (1423) arranged between the two vertical plates (1421), the two vertical plates (1421) are connected with the inner wall of the cavity of the first submerged body (122), the connecting rod (1422) is parallel to the axis of the first submerged body (122), the supporting platform (1423) is slidably and fixedly installed on the connecting rod (1422), the lower end of the first towing rod (221) is rotatably connected with the supporting platform (1423), and the rotation axis is perpendicular to the axis of the first submerged body (122) and is parallel to the fixed frame beam (11);

the second sheet structure (13) is identical in structure to the first sheet structure (12).

7. The small waterplane area catamaran towing test apparatus according to claim 6, wherein in the first sheet structure (12), the first submerged body (122) is provided with a threaded hole therethrough, and after the support platform (1423) is adjusted in position along the connecting rod (1422), a screw is engaged with the threaded hole and the support platform (1423) is pressed against;

the second sheet structure (13) is of the same construction as the first sheet structure (12).

8. The small waterplane area catamaran drag test apparatus according to any one of claims 4 to 7, wherein the measuring assembly comprises a drag force measuring device (30), the drag force measuring device (30) comprises a support body (31), a vertical sleeve (32), a pull pressure sensor (33), an elastic sheet (34), a pneumatic clamp (35), a slide block (36) and a slide rod (37);

the top of the supporting body (31) is fixedly connected with the power device (21);

the pneumatic clamp (35) and the sliding rod (37) are fixed on the support body (31), and the sliding rod (37) is consistent with the longitudinal direction of the small waterplane catamaran model;

the sliding block (36) is slidably sleeved on the sliding rod (37), and two ends of the sliding rod (37) are respectively and fixedly provided with one elastic sheet (34) for preventing the sliding block (36) from sliding out of the sliding rod (37);

one end of the tension and pressure sensor (33) is connected with the sliding rod (37), the other end of the tension and pressure sensor is connected with the sliding block (36), and the tension and pressure direction of the tension and pressure sensor (33) is consistent with the longitudinal direction of the small waterplane area catamaran model and is used for measuring the dragging force of the dragging device;

the vertical sleeve (32) is fixed at one end of the sliding block (36), and the vertical rod (224) is inserted into the vertical sleeve (32) to form sliding fit;

when the pneumatic clamp (35) is opened, the sliding block (36) can slide along the sliding rod (37); when the pneumatic clamp (35) is closed, the sliding block (36) is clamped, so that the sliding block (36) cannot slide along the sliding rod (37).

9. The small waterplane area catamaran drag test apparatus according to claim 8, wherein the drag force measuring device (30) further includes a laser displacement sensor (38) installed on the support body (31) to face the upper end face of the vertical rod (224) at a predetermined distance.

10. The small waterplane area catamaran towing test apparatus according to any one of claims 1 to 7, wherein the measurement assembly includes a tilt sensor (40), and the tilt sensor (40) is disposed on the fixed frame beam (11) and is configured to measure a pitch angle of the small waterplane area catamaran model.

11. The small waterplane area catamaran towing test apparatus of any one of claims 1 to 7, wherein the traverse preventing heeling structure (23) comprises a rectangular frame (231) and a guide bar (232);

the rectangular frame (231) is fixedly connected with the fixed frame beam (11), a rectangular hole extending along the longitudinal direction is formed in the rectangular frame (231), the longitudinal center line of the rectangular hole is located in the longitudinal section of the middle position of the fixed frame beam (11), the upper end of the guide rod (232) is fixedly connected with the power device (21), and the lower end of the guide rod (232) is inserted into the rectangular hole of the rectangular frame (231).

12. A small waterplane area catamaran towing test method using the small waterplane area catamaran towing test apparatus according to any one of claims 1 to 11, the test method comprising the steps of:

determining the sizes of all parts of a small waterplane area catamaran model according to the actual size of the small waterplane area catamaran and a preset scale ratio, fixedly connecting a first sheet structure (12) and a second sheet structure (13) with a fixed frame beam (11) according to the interval and the actual inclination angle after the first sheet structure and the second sheet structure are scaled in equal proportion, and sequentially assembling other parts according to the connection relation;

determining and adjusting the draft and the floating state of the small waterplane area catamaran model according to the draft and the floating state of the actual small waterplane area catamaran and the preset scale ratio;

according to the formula

Determining the towing speed V of a catamaran model with a small water plane _m Wherein λ is a reduction ratio, V _s Is the actual speed of the small waterplane area catamaran, the speed V _s Selecting a plurality of speed points within a predetermined range according to a predetermined interval, and correspondingly obtaining a plurality of dragging speeds V _m ；

For a plurality of towing speeds V in sequence _m Carry out the measurementStarting a power device (21) to drag the small waterplane area catamaran model to move according to a preset track in a test pool, acquiring at least a drag force and a longitudinal inclination angle and a heave capacity of the small waterplane area catamaran model when the small waterplane area catamaran model accelerates to a set drag speed, completing a drag speed test, and repeating the steps until all drag speed points are tested;

and after the test is finished, analyzing the acquired data.

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