A high-speed heavy model delivery test method for conventional missiles and arrows

Abstract

A high-speed heavy model release test method for conventional projectiles and arrows belongs to the technical field of wind tunnel release test. First, the model scale of the projectile model is determined, the design quality of the projectile model is determined, and the feasibility of the design density ratio between the projectile model and the real projectile model is judged; then the initial average density of the projectile model is determined, the manufacturing material is selected, and a digital model is built according to the initial parameters of the projectile model, and then the digital model is reduced in weight until the mass, center of mass position, axial inertia, pitch and yaw inertia and moment of inertia of the digital model are all equal to the design values, and the final design model of the iterative design is obtained, and finally the actual projectile model is manufactured, and the mass, center of mass, axial inertia, pitch and yaw inertia of the actual projectile model are measured and fine-tuned until each parameter meets the design requirements. The problem that the high-speed heavy model release test of conventional projectiles and arrows is difficult to apply in engineering is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of wind tunnel release test, and in particular relates to a high-speed heavy model release test method for conventional missile and arrow release objects. Background Art

[0002] In the wind tunnel scaled release test, the model of the object to be released must not only meet the similarity of geometric shape, but also its mass characteristics, namely mass, center of mass, and inertia, must meet certain similarity conditions. There are two types of model scaled similarity relationships for high-speed release tests, one is light model similarity and the other is heavy model similarity. The separation trajectory results obtained by light model similarity do not strictly simulate the normal displacement of the object to be released, and the trajectory results need to be corrected. The separation trajectory obtained by heavy model similarity is strictly similar to the actual separation situation. Therefore, when the model has the design and processing conditions, the heavy model method is usually preferred.

[0003] However, when conducting heavy model similarity, the mass of the delivery model is scaled according to the product of the speed-pressure ratio and the square of the reduction ratio, while the volume of the model is scaled according to the cube of the reduction ratio. Therefore, under normal circumstances, the density of the delivery model of the heavy model method is much greater than the actual delivery object. The larger the reduction ratio, the greater the model density. At present, China has only conducted high-speed heavy model delivery tests on delivery objects with very small physical density such as empty auxiliary fuel tanks. For missiles, pods and other conventional density missiles and arrows, high-speed heavy model delivery tests have never been conducted. The corresponding test capabilities are not available. Summary of the invention

[0004] The purpose of the present invention is to provide a high-speed heavy model delivery test method for conventional projectiles and arrows, so as to solve the problem that the prior art does not have the ability to perform high-speed heavy model delivery tests. The technical solution adopted by the present invention is as follows:

[0005] A high-speed heavy model drop test method for conventional missile and arrow projectiles, wherein the drop test is conducted in a test section of a continuous wind tunnel, a carrier model is supported in the test section, and the missile and arrow model is arranged in the carrier model, comprising the following steps:

[0006] Step 1: Determine the scale of the projectile model, determine the design quality of the projectile model, and judge the feasibility of the design density ratio between the projectile model and the real projectile;

[0007] Step 2: first determine the initial average density of the projectile and arrow model, select the manufacturing material, and perform digital modeling based on the initial parameters of the projectile and arrow model, then reduce the weight of the digital model until the mass, center of mass position, axial inertia, and pitch and yaw inertia of the digital model are all equal to the design values, and obtain the iterative final design model. Finally, manufacture the projectile and arrow model, measure and fine-tune the mass, center of mass position, axial inertia, pitch and yaw inertia of the projectile and arrow model, until the above parameters meet the design requirements;

[0008] Step 3: Protect the high-speed camera installed in the wind tunnel room.

[0009] Furthermore, the specific steps of step one are:

[0010] Step 1.1, according to the size of the test section and the size of the real missile and arrow drop objects, determine the model scale and design volume of the missile and arrow model and the carrier aircraft model, so that the carrier aircraft model meets the model length, blockage and video measurement field requirements of the drop test. In the drop test, the Mach number of the test section is set to be less than or equal to 1.5, the blockage of the carrier aircraft model is designed to be less than or equal to 5%, and the model length of the carrier aircraft model is designed to be less than or equal to 70% of the width of the test section;

[0011] Step 1.2: In the wind tunnel operation envelope, the rated minimum total pressure of the wind tunnel under the test Mach number is increased by 5000Pa to 10000Pa and used as the allowable minimum total pressure of the wind tunnel for the launch test. The allowable maximum total pressure of the wind tunnel is determined by the wind tunnel operation envelope. The allowable minimum total pressure of the wind tunnel and the allowable maximum total pressure of the wind tunnel determine the allowable total pressure range of the wind tunnel for the launch test.

[0012] Step 1.3, first select the applied total pressure value within the allowable total pressure range of the wind tunnel, and determine the design mass and design inertia of the projectile model based on the applied total pressure value and the model reduction ratio, and then obtain the design density ratio between the projectile model and the real projectile according to the mass relationship between the design mass and the real projectile;

[0013] The design density ratio is equal to the mass ratio K between the projectile model 3 and the real projectile-like projectile. m， K m Determined according to the following formula:

[0014] K m =K1 2 *K P ;

[0015] Where K1 is the model scale, K P is the total pressure ratio;

[0016] K1 is determined according to the following formula:

[0017] ;

[0018] Where, L m is the length of the projectile model 3, L s The length of the actual projectile or arrow;

[0019] K P Determined according to the following formula:

[0020] ;

[0021] Where P m is the total pressure in the wind tunnel, P s is the total atmospheric pressure in actual flight conditions;

[0022] If the design density ratio is less than or equal to 12, proceed to step 2; if the design density ratio is greater than 12, reduce the selected application total pressure value within the allowable total pressure range of the wind tunnel, and redetermine the design density ratio of the missile model until the design density ratio is less than or equal to 12. If the selected application total pressure value is the minimum allowable total pressure of the wind tunnel and the design density ratio is still greater than 12, first reduce the model scale within the model scale range that meets step 1.1, and then redetermine the design density ratio of the missile model until the design density ratio is less than or equal to 12.

[0023] Furthermore, in step 1.1, the model blockage degree of the missile model is designed to be 2% to 3%.

[0024] Furthermore, the specific steps of step 2 are:

[0025] Step 2.1, according to the design volume and design mass of the projectile-arrow model, determine the design average density of the projectile-arrow model, the initial average density of the projectile-arrow model is 1.2 to 1.5 times the design average density, select the manufacturing materials of each component of the projectile-arrow model according to the initial average density, and obtain the initial mass of the projectile-arrow model;

[0026] Step 2.2, digitally model the projectile and arrow model according to the selected manufacturing material and the designed external dimensions of the projectile and arrow model, measure the digital model mass and the digital model center of mass position, and compare them with the designed mass and the designed center of mass position. According to the deviation between the digital model center of mass position and the designed center of mass position, and the difference between the digital model mass and the designed mass, reduce the weight of the heavier side of the digital model, so that the center of mass position of the digital model after weight reduction coincides with the designed center of mass position, and the digital model mass is equal to the designed mass;

[0027] Step 2.3, give priority to adjusting the axial inertia of the digital model, and compare the difference between the axial inertia of the digital model and the design inertia. If the axial inertia of the digital model is less than the design inertia, readjust the weight reduction position in step 2.2 so that the weight reduction area is closer to the axis, so that the axial inertia value of the digital model increases. If the axial inertia of the digital model is still less than the design inertia, design the digital model shell of the missile model as a multi-layer structure, increase the material density of the outer layer of the digital model, and further reduce the weight of the inside of the digital model until the axial inertia of the digital model is equal to the design inertia, and the mass of the digital model and the digital model are equal. The center of mass position of the model meets the requirements in step 2.2; if the axial inertia of the digital model is greater than the design inertia, readjust the weight reduction position in step 2.2 so that the weight reduction area is closer to the outer layer of the digital model to reduce the axial inertia of the digital model. If the axial inertia of the digital model is still greater than the design inertia, design the digital model shell of the missile model as a multi-layer structure, reduce the material density of the outer layer of the digital model, and use high-density materials to fill the inside of the digital model until the axial inertia of the digital model is equal to the design inertia, and the mass of the digital model and the center of mass position of the digital model meet the requirements in step 2.2;

[0028] Step 2.4, then adjust the pitch and yaw inertia of the digital model, measure the pitch and yaw inertia of the digital model, and compare them with the pitch and yaw inertia design values ​​of the missile model. If the measured values ​​of the pitch and yaw inertia of the digital model are greater than the pitch and yaw inertia design values ​​of the missile model, then reduce the mass at both ends of the digital model and increase the corresponding mass in the middle area; if the measured values ​​of the pitch and yaw inertia of the digital model are less than the pitch and yaw inertia design values ​​of the missile model, then increase the mass at both ends of the digital model and remove the corresponding mass in the middle area of ​​the digital model, so that the measured values ​​of the pitch and yaw inertia of the digital model are equal to the pitch and yaw inertia design values ​​of the missile model, repeat steps 2.2 to 2.4 until the mass, center of mass position, axial inertia, and pitch and yaw inertia of the digital model are all equal to the design values, and the iterative final design model is obtained;

[0029] Step 2.5: Manufacture the actual missile model according to the final design model, process the components of the missile model according to the correct materials and structural internal and external surfaces, and re-measure the weight of each component to ensure that the quality error of each component is within the allowable error range of the design;

[0030] Step 2.6, assemble the projectile and arrow model, measure the mass, center of mass position, axial inertia, pitch and yaw direction inertia and moment of inertia of the projectile and arrow model, and compare them with the corresponding design values ​​of the projectile and arrow model. If the mass, center of mass position, axial inertia and pitch and yaw direction inertia measured values ​​of the projectile and arrow model meet the design requirements, the projectile and arrow model is completed; if the mass, center of mass position, axial inertia and pitch and yaw direction inertia measured values ​​of the projectile and arrow model do not meet the design requirements, firstly analyze the area where weight reduction or weight increase is required for the projectile and arrow model according to the deviation, adopt the same method as modifying the numerical model, and modify the projectile and arrow model to reduce or increase weight, and then repeat steps 2.5 to 2.6 until the mass, center of mass position, axial inertia and pitch and yaw direction inertia measured values ​​of the projectile and arrow model meet the design requirements.

[0031] Furthermore, in step 2.1, if the initial average density is greater than or equal to 9g / cm³, the body and counterweight of the projectile model are made of tungsten-copper alloy; if the initial average density is less than 9g / cm³, one or more of steel, aluminum alloy and resin materials are used for the projectile model.

[0032] Furthermore, the specific steps of step three are:

[0033] Step 3.1, make a camera protection device, the camera protection device includes a box body, the box body is fixed on the outer wall of the test section, the box wall connected to the test section is defined as the proximal wall panel of the box body, the box wall away from the test section is defined as the distal wall panel, the distal wall panel is provided with an air intake quick-connect connector, a temperature sensor, a pressure sensor, an exhaust quick-connect connector and a plurality of through-thread connectors, the proximal wall panel is provided with a window frame opening, the window frame opening is matched with the observation window of the test section, the air intake quick-connect connector is connected to the air intake pipeline of the wind tunnel, the exhaust quick-connect connector is connected to the exhaust pipeline of the wind tunnel, the pressure sensor and the temperature sensor are electrically connected to the control system of the continuous wind tunnel respectively, and a plurality of measurement and control line through-thread connectors are used for threading cables;

[0034] Step 3.2, fix the high-speed camera in the box, with the air intake quick-connect connector facing away from the high-speed camera, and use the high-speed camera to shoot the release of the missile model through the observation window.

[0035] Further, the high-speed camera is fixed in the box body through a camera mounting seat, and the camera mounting seat includes a fixing plate and an L-shaped adjustment plate, the fixing plate is arranged along the cross section of the test section, and a plurality of horizontally arranged first adjustment holes are provided on the fixing plate, and the L-shaped adjustment plate includes a vertical portion and a horizontal portion, and a first long circular arc hole and a positioning hole are opened on the vertical portion, and the positioning hole is located at the arc center of the first long circular arc hole, and the arc center angle of the first long circular arc hole is 180°, and the radius of the first long circular arc hole is equal to the spacing between two adjacent first adjustment holes, and any one of the plurality of first adjustment holes is used as a lateral connection hole, and the lateral connection hole is connected to the positioning hole by bolts, and a first adjustment hole adjacent to the lateral connection hole is connected to the first long circular arc hole by bolts;

[0036] The transverse portion is provided with an oblong hole in the same direction as the length of the test section, and adjustment hole groups are symmetrically provided on both sides of the oblong hole. The adjustment hole group is composed of a plurality of second adjustment holes arranged at intervals along the length direction of the oblong hole, and the spacing between the two groups of the adjustment hole groups is equal to the spacing between the two connected second adjustment holes. Four second adjustment holes arranged in a square in any manner in the two groups of the adjustment hole groups are used as an axial connection hole group, and a positioning screw hole is provided on the mounting flange of the high-speed camera. Four second oblong holes are evenly distributed on the outer circumference of the positioning screw hole. The positioning screw hole is connected to the oblong hole by bolts, and the four second adjustment holes in the axial connection hole group are connected to the four second oblong holes by bolts in a one-to-one correspondence.

[0037] Furthermore, the distal wall panel and the proximal wall panel are connected through four side wall panels to form a rectangular box.

[0038] Furthermore, the distal wall panel and the four side wall panels are sealed and connected via a silicone rubber pad, the proximal wall panel and the four side wall panels are sealed and connected via a silicone rubber pad, the four side wall panels are sealed and connected in turn via silicone rubber pads, and a silicone rubber pad is provided between the window frame opening and the observation window.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention is suitable for conducting a release test in a continuous wind tunnel. The negative total pressure blowing characteristic of the continuous wind tunnel is utilized to greatly reduce the theoretical density design value of the heavy model method scaled release model. Then, a design and processing method for high-density model quality characteristics is proposed, which solves the problem that the heavy model method scaled model of missile and arrow droplets in a temporary wind tunnel has a large specific gravity and cannot meet the design and processing feasibility requirements. Finally, special engineering problems that need to be faced in conducting release tests in a continuous wind tunnel, such as wind tunnel equipment protection, release model recovery, and high-speed camera protection, are proposed. Through the above steps, the problem that high-speed heavy model release tests of conventional missile and arrow droplets are difficult to be applied in engineering is finally solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1is a flow chart of the method of the present invention;

[0042] Figure 2 It is a front view of the device for launching the test of the present invention;

[0043] Figure 3 It is a left view of the device for the launch test of the present invention;

[0044] Figure 4 It is a schematic diagram of the structure of the camera protection device;

[0045] Figure 5 It is a schematic diagram of the structure of the camera mount;

[0046] Figure 6 This is the front view of the mounting flange of the high-speed camera.

[0047] In the figure, 1. test section, 2. carrier aircraft model, 3. missile model, 4. observation window, 5. video measurement field of view, 6. high-speed camera, 7. box, 8. side wall plate, 9. far wall plate, 10. near wall plate, 11. exhaust quick plug connector, 12. temperature sensor, 13. through-thread connector, 14. intake quick plug connector, 15. camera mounting seat, 16. fixing plate, 17. L-shaped adjustment plate, 18. first long arc hole, 19. positioning hole, 20. first adjustment hole, 21. second adjustment hole, 22. second long arc hole, 23. positioning screw hole, 24. pressure sensor, 25. long circular hole. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0049] The connection mentioned in the present invention is divided into fixed connection and detachable connection. The fixed connection is a non-detachable connection including but not limited to conventional fixed connection methods such as folding connection, rivet connection, bonding connection and welding connection. The detachable connection includes but not limited to conventional detachable methods such as bolt connection, snap connection, pin connection and hinge connection. When the specific connection method is not clearly defined, it is assumed that at least one connection method can be found in the existing connection methods to achieve the function, and those skilled in the art can choose according to their needs. For example: welding connection is selected for fixed connection, and bolt connection is selected for detachable connection.

[0050] The present invention will be further described in detail below in conjunction with the accompanying drawings. The following embodiments are provided to explain the present invention, but the present invention is not limited to the following embodiments.

[0051] Example: Figure 1 to Figure 6 As shown, a high-speed heavy model release test method for conventional missile and arrow projectiles is performed in a test section 1 of a continuous wind tunnel, a carrier model 2 is supported in the test section 1, and a missile and arrow model 3 is arranged in the carrier model 2, comprising the following steps:

[0052] Step 1: determine the scale of the projectile model 3, determine the design quality of the projectile model 3, and judge the feasibility of the design density ratio between the projectile model 3 and the real projectile;

[0053] Step 2: first determine the initial average density of the projectile and arrow model 3, select the manufacturing material, and perform digital modeling based on the initial parameters of the projectile and arrow model 3, then reduce the weight of the digital model until the mass, center of mass position, axial inertia, and pitch and yaw inertia of the digital model are all equal to the design values, and obtain the iterative final design model, and finally manufacture the projectile and arrow model 3, measure and fine-tune the mass, center of mass position, axial inertia, pitch and yaw inertia of the projectile and arrow model 3, until the above parameters meet the design requirements;

[0054] Step 3: Protect the high-speed camera 6 installed in the wind tunnel chamber.

[0055] The specific steps of step one are:

[0056] Step 1.1, according to the size of the test section 1 and the size of the real missile and arrow drop objects, determine the model scale and design volume of the missile and arrow model 3 and the carrier model 2, so that the carrier model 2 meets the model extension, blockage and video measurement field of view 5 requirements of the drop test, Figure 2 A schematic diagram of the aircraft model 2 supported in the test section 1 during the drop test is given. The dotted line represents the range of the video measurement field of view 5. The video measurement field of view 5 should be able to fully capture the suspension state of the aircraft model 2 and the drop trajectory of the missile model 3 as well as the separation space range required by the test. Usually, this range is given by the test task book. If the task book is not given, the separation space range is considered to be not less than 2 times the length of the missile model 3 in the normal and axial directions. It is a known parameter before the drop test. In the drop test, the Mach number of the test section 1 is set to be less than or equal to 1.5, then the blockage degree of the aircraft model 2 is designed to be less than or equal to 5%, and the model extension of the aircraft model 2 is designed to be less than or equal to 70% of the width of the test section 1;

[0057] Step 1.2: In the wind tunnel operation envelope, the rated minimum total pressure of the wind tunnel under the test Mach number is increased by 5000Pa to 10000Pa and used as the allowable minimum total pressure of the wind tunnel for the launch test. The allowable maximum total pressure of the wind tunnel is determined by the wind tunnel operation envelope. The allowable minimum total pressure of the wind tunnel and the allowable maximum total pressure of the wind tunnel determine the allowable total pressure range of the wind tunnel for the launch test.

[0058] Step 1.3, first select the applied total pressure value within the allowable total pressure range of the wind tunnel, and determine the design mass and design inertia of the projectile model 3 according to the applied total pressure value and the model reduction ratio, and then obtain the design density ratio between the projectile model 3 and the real projectile and arrow droplets according to the mass relationship between the design mass and the real projectile and arrow droplets;

[0059] The design density ratio is equal to the mass ratio K between the projectile model 3 and the real projectile-like projectile. m， K m Determined according to the following formula:

[0060] K m =K1 2 *K P ;

[0061] Where K1 is the model scale, K P is the total pressure ratio;

[0062] K1 is determined according to the following formula:

[0063] ;

[0064] Where, L m is the length of the projectile model 3, L s The length of the actual projectile or arrow;

[0065] K P Determined according to the following formula:

[0066] ;

[0067] Where P m is the total pressure in the wind tunnel, P s is the total atmospheric pressure in actual flight conditions;

[0068] If the design density ratio is less than or equal to 12, proceed to step 2; if the design density ratio is greater than 12, reduce the selected application total pressure value within the allowable total pressure range of the wind tunnel, and redetermine the design density ratio of the missile model 3 until the design density ratio is less than or equal to 12. If the selected application total pressure value is the minimum allowable total pressure of the wind tunnel and the design density ratio is still greater than 12, first reduce the model scale within the model scale range that meets step 1.1, and then redetermine the design density ratio of the missile model 3 until the design density ratio is less than or equal to 12.

[0069] In step 1.1, the model blockage degree of the missile model is designed to be 2% to 3%.

[0070] The specific steps of step 2 are:

[0071] Step 2.1, according to the design volume and design mass of the projectile and arrow model 3, determine the design average density of the projectile and arrow model 3, the initial average density of the projectile and arrow model 3 is 1.2 to 1.5 times the design average density, select the manufacturing materials of the various components of the projectile and arrow model 3 according to the initial average density, and obtain the initial mass of the projectile and arrow model 3; if the initial average density is greater than or equal to 9g / cm³, the spiral body and counterweight of the projectile and arrow model 3 are made of tungsten-copper alloy material; if the initial average density is less than 9g / cm³, the projectile and arrow model 3 is made of one or more of steel, aluminum alloy and resin materials.

[0072] Step 2.2, digital modeling of the projectile and arrow model 3 is performed according to the selected manufacturing material and the design external dimensions of the projectile and arrow model 3, the digital model mass and the digital model center of mass position are measured, and compared with the design mass and the design center of mass position, and according to the deviation between the digital model center of mass position and the design center of mass position, and the difference between the digital model mass and the design mass, the weight of the heavier side of the digital model is reduced, so that the center of mass position of the digital model after weight reduction coincides with the design center of mass position, and the digital model mass is equal to the design mass;

[0073] If the initial average density is greater than or equal to 9g / cm³, and usually in order to match the center of mass position and inertia of the projectile and arrow model, the main material density of the projectile and arrow model 3 should be greater than the designed average density, so conventional metal materials cannot meet the design requirements of the projectile and arrow model 3, then the spiral body and counterweight of the projectile and arrow model 3 are made of tungsten-copper alloy material; due to the low density and poor toughness of tungsten-copper alloy material, it is suitable for processing model parts with simple shapes, but not suitable for processing thin-walled materials such as projectile wings. Conventional metal processing technology can be used during processing. If the initial average density is less than 9g / cm³, then the projectile and arrow model 3 uses one or more of steel, aluminum alloy and resin materials.

[0074] Step 2.3, give priority to adjusting the axial inertia of the digital model, and compare the difference between the axial inertia of the digital model and the design inertia. If the axial inertia of the digital model is less than the design inertia, readjust the weight reduction position in step 2.2 so that the weight reduction area is closer to the axis, so that the axial inertia value of the digital model increases. If the axial inertia of the digital model is still less than the design inertia, design the digital model shell of the missile model 3 as a multi-layer structure, increase the material density of the outer layer of the digital model, and further reduce the weight of the inside of the digital model until the axial inertia of the digital model is equal to the design inertia, and the mass of the digital model and the digital model are equal. The center of mass position of the model meets the requirements in step 2.2; if the axial inertia of the digital model is greater than the design inertia, the weight reduction position in step 2.2 is readjusted so that the weight reduction area is closer to the outer layer of the digital model to reduce the axial inertia of the digital model. If the axial inertia of the digital model is still greater than the design inertia, the digital model shell of the missile model 3 is designed as a multi-layer structure, the material density of the outer layer of the digital model is reduced, and high-density materials are used to fill the inside of the digital model until the axial inertia of the digital model is equal to the design inertia, and the mass of the digital model and the center of mass position of the digital model meet the requirements in step 2.2;

[0075] Step 2.4, then adjust the pitch and yaw inertia of the digital model, measure the pitch and yaw inertia of the digital model, and compare them with the pitch and yaw inertia design values ​​of the missile model 3. If the measured values ​​of the pitch and yaw inertia of the digital model are greater than the pitch and yaw inertia design values ​​of the missile model 3, then reduce the mass at both ends of the digital model and increase the corresponding mass in the middle area; if the measured values ​​of the pitch and yaw inertia of the digital model are less than the pitch and yaw inertia design values ​​of the missile model 3, then increase the mass at both ends of the digital model and remove the corresponding mass in the middle area of ​​the digital model, so that the measured values ​​of the pitch and yaw inertia of the digital model are equal to the pitch and yaw inertia design values ​​of the missile model 3, repeat steps 2.2 to 2.4 until the mass, center of mass position, axial inertia, and pitch and yaw inertia of the digital model are all equal to the design values, and the iterative final design model is obtained;

[0076] Step 2.5, manufacture the actual object of the missile model 3 according to the final design model, process the components of the missile model 3 in place according to the correct materials and structural inner and outer surfaces, and re-measure the weight of each component to ensure that the quality error of each component is within the allowable error range of the design;

[0077] Step 2.6, assemble the projectile and arrow model 3, measure the mass, center of mass position, axial inertia, pitch and yaw direction inertia and moment of inertia of the projectile and arrow model 3, and compare them with the corresponding design values ​​of the projectile and arrow model 3. If the mass, center of mass position, axial inertia and pitch and yaw direction inertia measured values ​​of the projectile and arrow model 3 meet the design requirements, the projectile and arrow model 3 is completed; if the mass, center of mass position, axial inertia and pitch and yaw direction inertia measured values ​​of the projectile and arrow model 3 do not meet the design requirements, firstly analyze the area where weight reduction or weight increase is required for the projectile and arrow model 3 according to the deviation situation, adopt the same method as modifying the numerical model, and modify the projectile and arrow model 3 to reduce or increase weight, and then repeat steps 2.5 to 2.6 until the mass, center of mass position, axial inertia and pitch and yaw direction inertia measured values ​​of the projectile and arrow model 3 meet the design requirements.

[0078] The specific steps of step three are:

[0079] Step 3.1, make a camera protection device, the camera protection device includes a box body 7, the box body 7 is fixed on the outer wall of the test section 1, the box wall of the box body 7 connected to the test section 1 is defined as the proximal wall panel 10 of the box body 7, the box wall of the box body 7 away from the test section 1 is defined as the distal wall panel 9, the distal wall panel 9 is provided with an air intake quick plug connector 14, a temperature sensor 12, a pressure sensor 24, an exhaust quick plug connector 11 and a plurality of through-thread connectors 13, a window frame opening is opened on the proximal wall panel 10, the window frame opening is matched with the observation window 4 of the test section 1, the observation window 4 is arranged on the side wall panel of the test section 1, the air intake quick plug connector 14 is connected to the air intake pipeline of the wind tunnel, the exhaust quick plug connector 11 is connected to the exhaust pipeline of the wind tunnel, the pressure sensor 24 and the temperature sensor 12 are respectively electrically connected to the control system of the continuous wind tunnel, and a plurality of measurement and control line through-thread connectors 13 are used for threading cables; the structural schematic diagram of the camera protection device is shown in Figure 4 The box 7 is made of 7075 hard aluminum with a wall thickness of 6mm, a rib height of 10mm and a weight of about 10Kg. The airflow of the air inlet quick-connect connector 14 is blown directly to the inner shell of the box 1 to avoid blowing directly to the high-speed camera 6 or the cable, causing the high-speed camera 6 to vibrate or the cable to disturb, affecting the shooting. The pressure sensor 24 and the temperature sensor 12 are used to monitor the pressure and temperature in the box 1, and feed back to the control system to adjust the air supply pressure in real time to ensure that the box 1 is in a normal pressure state and the high-speed camera 6 operates normally. The pressure in the box 1 is always controlled at normal pressure, and the sealing and strength can be guaranteed under the external pressure of the box 0~0.4MPa (absolute pressure), and the maximum allowable leakage is 24L / min. The cables in the box 1 can be led out of the box 1 through the threaded connector 13. The reserved cable routing port allows the routing of 1 220V power cable, 1 network cable, 1 10mm air pipeline, and 2 data cables of the high-speed camera 6.

[0080] Step 3.2, fix the high-speed camera 6 in the box 7, with the air intake quick-connect connector 14 facing away from the high-speed camera 6, and the high-speed camera 6 shoots the release of the missile model 3 through the observation window 4.

[0081] The high-speed camera 6 is fixed in the box body 7 through the camera mounting seat 15. The camera mounting seat 15 includes a fixing plate 16 and an L-shaped adjustment plate 17. The fixing plate 16 is arranged along the cross section of the test section 1. The fixing plate 16 is provided with a plurality of horizontally arranged first adjustment holes 20. The L-shaped adjustment plate 17 includes a vertical portion and a horizontal portion. The vertical portion is provided with a first long circular arc hole 18 and a positioning hole 19. The positioning hole 19 is located at the arc center of the first long circular arc hole 18. The arc center angle of the first long circular arc hole 18 is 180°, and the radius of the first long circular arc hole 18 is equal to the spacing between two adjacent first adjustment holes 20. Any one of the plurality of first adjustment holes 20 is used as a lateral connection hole. The lateral connection hole is connected to the positioning hole 19 by bolts, and a first adjustment hole 20 adjacent to the lateral connection hole is connected to the first long circular arc hole 18 by bolts.

[0082] The transverse portion is provided with an oblong hole 25 in the same direction as the length of the test section 1, and adjustment hole groups are symmetrically provided on both sides of the oblong hole 25. The adjustment hole group is composed of a plurality of second adjustment holes 21 arranged at intervals along the length direction of the oblong hole 25, and the spacing between the two groups of the adjustment hole groups is equal to the spacing between the two connected second adjustment holes 21. Four second adjustment holes 21 arranged in a square in any manner in the two groups of the adjustment hole groups are used as an axial connection hole group, and a positioning screw hole 23 is provided on the mounting flange of the high-speed camera 6. Four second oblong arc holes 22 are evenly distributed on the outer circumference of the positioning screw hole 23. The positioning screw hole 23 is connected to the oblong hole 25 by bolts, and the four second adjustment holes 21 in the axial connection hole group are connected to the four second oblong arc holes 22 by bolts in a one-to-one correspondence.

[0083] By adjusting the selected lateral connecting hole, the high-speed camera 6 can be adjusted to be closer to or farther away from the test section 1. The L-shaped adjustment plate 17 can rotate around the positioning hole 19 to adjust the pitch angle of the high-speed camera 6. The mounting flange of the high-speed camera 6 and the L-shaped adjustment plate 17 can be adjusted along the length direction of the test section 1, and the high-speed camera 6 can also be rotated around the positioning screw hole 23 to meet the position and angle adjustment of the high-speed camera 6.

[0084] The distal wall panel 9 and the proximal wall panel 10 are connected through four side wall panels 8 to form a rectangular box body 7 .

[0085] The distal wall panel 9 and the four side wall panels 8 are sealed and connected via a silicone rubber pad, the proximal wall panel 10 and the four side wall panels 8 are sealed and connected via a silicone rubber pad, and the four side wall panels 8 are sealed and connected in turn via silicone rubber pads. In order to prevent the optical glass from colliding with the window frame due to vibration or structural deformation, a silicone rubber pad is provided between the window frame opening and the observation window 4.

[0086] The present invention is suitable for conducting a release test in a continuous wind tunnel. The negative total pressure blowing characteristic of the continuous wind tunnel is utilized to greatly reduce the theoretical density design value of the heavy model method scaled release model. Then, a design and processing method for high-density model quality characteristics is proposed, which solves the problem that the heavy model method scaled model of missile and arrow droplets in a temporary wind tunnel has a large specific gravity and cannot meet the design and processing feasibility requirements. Finally, special engineering problems that need to be faced in conducting release tests in a continuous wind tunnel, such as wind tunnel equipment protection, release model recovery, and high-speed camera protection, are proposed. Through the above steps, the problem that high-speed heavy model release tests of conventional missile and arrow droplets are difficult to be applied in engineering is finally solved.

[0087] The above embodiments are merely exemplary descriptions of the present invention and do not limit its protection scope. Those skilled in the art may also make partial changes thereto, which are within the protection scope of the present invention as long as they do not exceed the spirit of the present invention.

Claims

1. A high-speed heavy model drop test method for conventional missile-like projectiles, wherein the drop test is conducted in a test section (1) of a continuous wind tunnel, a carrier model (2) is supported in the test section (1), and a missile model (3) is arranged in the carrier model (2), characterized in that: The following steps are involved: Step 1: determine the scale of the projectile model (3), determine the design quality of the projectile model (3), and judge the feasibility of the design density ratio between the projectile model (3) and the real projectile; Step 2: first determine the initial average density of the projectile and arrow model (3), select the manufacturing material, and perform digital modeling based on the initial parameters of the projectile and arrow model (3), then reduce the weight of the digital model until the mass, center of mass position, axial inertia, and pitch and yaw inertia of the digital model are all equal to the design values, and obtain the iterative final design model, and finally manufacture the projectile and arrow model (3), measure and fine-tune the mass, center of mass position, axial inertia, pitch and yaw inertia of the projectile and arrow model (3), until the above parameters meet the design requirements; Step 3: Protect the high-speed camera (6) installed in the wind tunnel chamber.

2. A high-speed heavy model delivery test method for conventional missiles and arrows according to claim 1, characterized in that: The specific steps of step one are: Step 1.1, according to the size of the test section (1) and the size of the real missile-like drop object, determine the model scale and design volume of the missile model (3) and the carrier model (2), so that the carrier model (2) meets the model extension, blockage and video measurement field of view (5) requirements of the drop test. In the drop test, the Mach number of the test section (1) is set to be less than or equal to 1.5, and the blockage of the carrier model (2) is designed to be less than or equal to 5%, and the model extension of the carrier model (2) is designed to be less than or equal to 70% of the width of the test section (1); Step 1.2: In the wind tunnel operation envelope, the rated minimum total pressure of the wind tunnel under the test Mach number is increased by 5000Pa to 10000Pa and used as the allowable minimum total pressure of the wind tunnel for the launch test. The allowable maximum total pressure of the wind tunnel is determined by the wind tunnel operation envelope. The allowable minimum total pressure of the wind tunnel and the allowable maximum total pressure of the wind tunnel determine the allowable total pressure range of the wind tunnel for the launch test. Step 1.3, first select an applied total pressure value within the allowable total pressure range of the wind tunnel, and determine the design mass and design inertia of the projectile model (3) based on the applied total pressure value and the model reduction ratio, and then obtain the design density ratio between the projectile model (3) and the real projectile according to the mass relationship between the design mass and the real projectile; The design density ratio is equal to the mass ratio K between the missile model (3) and the real missile-like projectile m， K m Determined according to the following formula: K m =K1 2 *K P ; Where K1 is the model scale, K P is the total pressure ratio; K1 is determined according to the following formula: ； Where, L m is the length of the projectile model (3), L s The length of the actual projectile or arrow; K P Determined according to the following formula: ； Where P m is the total pressure in the wind tunnel, P s is the total atmospheric pressure in actual flight conditions; If the design density ratio is less than or equal to 12, proceed to step 2; if the design density ratio is greater than 12, reduce the selected application total pressure value within the allowable total pressure range of the wind tunnel, and redetermine the design density ratio of the missile model (3) until the design density ratio is less than or equal to 12. If the selected application total pressure value is the minimum allowable total pressure of the wind tunnel and the design density ratio is still greater than 12, first reduce the model scale within the model scale range that satisfies step 1.1, and then redetermine the design density ratio of the missile model (3) until the design density ratio is less than or equal to 12.

3. A high-speed heavy model delivery test method for conventional projectiles and arrows according to claim 2, characterized in that: In step 1.1, the model blockage degree of the missile model (3) is designed to be 2% to 3%.

4. A high-speed heavy model delivery test method for conventional missiles and arrows according to claim 2, characterized in that: The specific steps of step 2 are: Step 2.1, according to the design volume and design mass of the projectile-arrow model (3), determine the design average density of the projectile-arrow model (3), the initial average density of the projectile-arrow model (3) is 1.2 to 1.5 times the design average density, select the manufacturing materials of each component of the projectile-arrow model (3) according to the initial average density, and obtain the initial mass of the projectile-arrow model (3); Step 2.2, digitally model the projectile and arrow model (3) according to the selected manufacturing material and the design external dimensions of the projectile and arrow model (3), measure the digital model mass and the digital model center of mass position, and compare them with the design mass and the design center of mass position; according to the deviation between the digital model center of mass position and the design center of mass position, and the difference between the digital model mass and the design mass, reduce the weight of the heavier side of the digital model, so that the center of mass position of the digital model after weight reduction coincides with the design center of mass position, and the digital model mass is equal to the design mass; Step 2.3, give priority to adjusting the axial inertia of the digital model, and compare the difference between the axial inertia of the digital model and the design inertia. If the axial inertia of the digital model is less than the design inertia, readjust the weight reduction position in step 2.2 so that the weight reduction area is closer to the axis, so that the axial inertia of the digital model increases. If the axial inertia of the digital model is still less than the design inertia, design the digital model shell of the missile model (3) as a multi-layer structure, increase the material density of the outer layer of the digital model, and further reduce the weight of the inside of the digital model until the axial inertia of the digital model is equal to the design inertia, and the mass of the digital model and the digital model are equal. The center of mass position of the model meets the requirements in step 2.2; if the axial inertia of the digital model is greater than the design inertia, the weight reduction position in step 2.2 is readjusted so that the weight reduction area is closer to the outer layer of the digital model to reduce the axial inertia of the digital model. If the axial inertia of the digital model is still greater than the design inertia, the digital model shell of the missile model (3) is designed as a multi-layer structure, the material density of the outer layer of the digital model is reduced, and high-density materials are used to fill the inside of the digital model until the axial inertia of the digital model is equal to the design inertia, and the mass of the digital model and the center of mass position of the digital model meet the requirements in step 2.2; Step 2.4, then adjust the pitch and yaw inertia of the digital model, measure the pitch and yaw inertia of the digital model, and compare them with the pitch and yaw inertia design values ​​of the missile model (3). If the measured pitch and yaw inertia of the digital model is greater than the pitch and yaw inertia design values ​​of the missile model (3), then reduce the mass at both ends of the digital model and increase the corresponding mass in the middle area; If the measured values ​​of the pitch and yaw inertia of the digital model are less than the designed values ​​of the pitch and yaw inertia of the missile model (3), the masses at both ends of the digital model are increased, and the corresponding masses are removed from the middle area of ​​the digital model, so that the measured values ​​of the pitch and yaw inertia of the digital model are equal to the designed values ​​of the pitch and yaw inertia of the missile model (3), and steps 2.2 to 2.4 are repeated until the mass, center of mass position, axial inertia, and pitch and yaw inertia of the digital model are all equal to the designed values, and the iterative final design model is obtained; Step 2.5, manufacturing the actual object of the missile model (3) according to the final design model, processing each component of the missile model (3) in place according to the correct material and structural inner and outer surfaces, and re-measuring the weight of each component to ensure that the mass error of each component is within the allowable error range of the design; Step 2.6, assemble the projectile and arrow model (3), measure the mass, center of mass position, axial inertia, pitch and yaw direction inertia and moment of inertia of the projectile and arrow model (3), and compare them with the design values ​​of the corresponding projectile and arrow model (3). If the mass, center of mass position, axial inertia and pitch and yaw direction inertia measured values ​​of the projectile and arrow model (3) meet the design requirements, the projectile and arrow model (3) is completed; if the mass, center of mass position, axial inertia and pitch and yaw direction inertia measured values ​​of the projectile and arrow model (3) do not meet the design requirements, firstly analyze the area of ​​the projectile and arrow model (3) that needs to be reduced or increased in weight according to the deviation situation, and modify the projectile and arrow model (3) to reduce or increase weight, and then repeat steps 2.5 to 2.6 until the mass, center of mass position, axial inertia and pitch and yaw direction inertia measured values ​​of the projectile and arrow model (3) meet the design requirements.

5. A high-speed heavy model delivery test method for conventional missiles and arrows according to claim 4, characterized in that: In step 2.1, if the initial average density is greater than or equal to 9 g / cm³, the body and counterweight of the projectile model (3) are made of tungsten-copper alloy material; if the initial average density is less than 9 g / cm³, the projectile model (3) is made of one or more of steel, aluminum alloy and resin material.

6. A high-speed heavy model delivery test method for conventional missiles and arrows according to claim 4, characterized in that: The specific steps of step three are: Step 3.1, manufacturing a camera protection device, the camera protection device comprising a box body (7), the box body (7) being fixed on the outer wall of the test section (1), the box wall of the box body (7) connected to the test section (1) being defined as the proximal wall plate (10) of the box body (7), the box wall of the box body (7) away from the test section (1) being defined as the distal wall plate (9), the distal wall plate (9) being provided with an air inlet quick-connect connector (14), a temperature sensor (12), a pressure sensor (24), and an exhaust quick-connect connector ( 11) and a plurality of threaded connectors (13), a window frame opening is provided on the proximal wall plate (10), the window frame opening cooperates with the observation window (4) of the test section (1), an air intake quick connector (14) is connected to the air intake pipeline of the wind tunnel, an exhaust quick connector (11) is connected to the exhaust pipeline of the wind tunnel, a pressure sensor (24) and a temperature sensor (12) are respectively electrically connected to the control system of the continuous wind tunnel, and a plurality of measurement and control line threaded connectors (13) are used for threading cables; Step 3.2, fix the high-speed camera (6) in the box (7), and direct the air inlet quick connector (14) away from the high-speed camera (6), and the high-speed camera (6) shoots the release of the missile model (3) through the observation window (4).

7. A high-speed heavy model delivery test method for conventional missiles and arrows according to claim 6, characterized in that: The high-speed camera (6) is fixed in the box (7) through a camera mounting seat (15), the camera mounting seat (15) includes a fixing plate (16) and an L-shaped adjustment plate (17), the fixing plate (16) is arranged along the cross section of the test section (1), the fixing plate (16) is provided with a plurality of horizontally arranged first adjustment holes (20), the L-shaped adjustment plate (17) includes a vertical portion and a horizontal portion, the vertical portion is provided with a first long arc hole (18) and a positioning hole (19), the positioning hole (19 ) is located at the arc center of the first long circular arc hole (18), the arc center angle of the first long circular arc hole (18) is 180°, and the radius of the first long circular arc hole (18) is equal to the spacing between two adjacent first adjustment holes (20), any one of the plurality of first adjustment holes (20) is used as a lateral connection hole, the lateral connection hole is connected to the positioning hole (19) by bolts, and a first adjustment hole (20) adjacent to the lateral connection hole is connected to the first long circular arc hole (18) by bolts; The transverse portion is provided with an oblong hole (25) in the same direction as the length of the test section (1), and adjustment hole groups are symmetrically provided on both sides of the oblong hole (25), the adjustment hole group consisting of a plurality of second adjustment holes (21) arranged at intervals along the length direction of the oblong hole (25), the spacing between the two groups of the adjustment hole groups being equal to the spacing between two connected second adjustment holes (21), and four second adjustment holes (21) arranged in a square in any order in the two groups of the adjustment hole groups are used as an axial connection hole group, a positioning screw hole (23) is provided on the mounting flange of the high-speed camera (6), and four second oblong arc holes (22) are evenly distributed on the outer circumference of the positioning screw hole (23), the positioning screw hole (23) is connected to the oblong hole (25) by bolts, and the four second adjustment holes (21) in the axial connection hole group are connected to the four second oblong arc holes (22) by bolts in a one-to-one correspondence.

8. A high-speed heavy model delivery test method for conventional missiles and arrows according to claim 6, characterized in that: The distal wall panel (9) and the proximal wall panel (10) are connected via four side wall panels (8) to form a rectangular box body (7).

9. A high-speed heavy model delivery test method for conventional projectiles and arrows according to claim 8, characterized in that: The distal wall plate (9) and the four side wall plates (8) are sealed and connected via a silicone rubber pad, the proximal wall plate (10) and the four side wall plates (8) are sealed and connected via a silicone rubber pad, the four side wall plates (8) are sealed and connected in sequence via silicone rubber pads, and a silicone rubber pad is provided between the window frame opening and the observation window (4).

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