A semi-submerged solid rocket engine deep-water thrust test device

Abstract

The present invention discloses a semi-submerged solid rocket engine deep-water thrust test device, which belongs to the field of underwater autonomous power launch weapon thrust testing. The present invention mainly consists of a high-pressure water tank, a flexible interface, a solid rocket engine to be tested, a high-precision tension and pressure sensor, and a sensor mounting stand. The high-pressure water tank consists of three parts: a water tank body, a water tank top cover, and a sensor mounting stand guide rail. The solid rocket engine to be tested consists of a solid rocket engine head and a solid rocket engine body. The flexible interface consists of an inner flange, an outer flange, and a number of elastic parts and reinforcement parts located therebetween. The present invention semi-submerges the solid rocket engine in water by adopting a flexible interface, so that the engine can work in a simulated deep-water environment while the test equipment is in a normal pressure atmospheric environment, avoiding strict waterproofing of the equipment, further simplifying the test process, and avoiding thrust test failures due to waterproofing failure.

Description

Technical Field

[0001] The present invention belongs to the field of underwater autonomous power launch weapon thrust testing, and in particular relates to a solid rocket engine dynamic thrust testing device for simulating deep water conditions. Background Art

[0002] In recent years, underwater high-speed weapons have received increasing attention from major maritime powers. The power systems of related weapons mostly use solid rocket engines. The application of this type of underwater high-speed weapons has gradually developed into deeper waters. Therefore, thrust testing of solid rocket engines under simulated deep-water conditions has become an important part of underwater high-speed weapon performance verification.

[0003] Thrust testing of solid rocket motors operating in deepwater conditions is far more difficult than ground-based thrust testing. This is due to the complex interaction between the water environment and the high-temperature, high-speed combustion gases emitted by the engine exhaust. This interaction can cause a certain degree of unsteady oscillation in the engine thrust. Furthermore, if a traditional solid rocket motor thrust test bench is used, the entire test system will be submerged in water, requiring certain test equipment to be waterproofed. Furthermore, ensuring the normal operation of all test equipment in a deepwater, high-pressure environment is extremely difficult, further complicating the testing process and potentially leading to test failure due to waterproofing failure. Therefore, there is an urgent need for a deepwater thrust test device for solid rocket motors that can avoid immersing the test equipment in water. Summary of the Invention

[0004] The main purpose of the present invention is to provide a semi-submerged solid rocket engine deep-water thrust test device, which ensures that the test equipment is in a normal pressure atmospheric environment while ensuring that the solid rocket engine operates in a simulated deep-water environment, so as to simplify the waterproofing treatment of the test equipment and avoid test failures caused by waterproof failure of the equipment.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] The invention discloses a semi-submerged solid rocket engine deep-water thrust test device, which is mainly composed of a high-pressure water tank, a flexible interface, a tested solid rocket engine, a high-precision tension and pressure sensor, and a sensor mounting stand.

[0007] The high-pressure water tank consists of three parts: the water tank body, the water tank top cover and the sensor mounting stand guide rail. The water tank top cover and the water tank body are connected by a flange, and the sensor mounting stand guide rail is fixedly connected to the water tank body; the water tank top cover is provided with a water inlet, an air inlet, an exhaust port and a cable opening; an opening is provided in the center of the bottom wall of the water tank body and in the lower position of the side wall for connecting the flexible interface; an observation window is provided on the side wall of the water tank body, and a drain outlet is provided on the edge of the bottom wall.

[0008] The solid rocket motor under test consists of a solid rocket motor head and a solid rocket motor body, which are fixedly connected by a flange. The radial and torsional movement of the solid rocket motor under test is restricted by a gantry located inside a high-pressure water tank.

[0009] The flexible interface consists of an inner flange, an outer flange, and several elastic parts and reinforcements located between them. The inner flange, outer flange, elastic parts, and reinforcements are bonded together with a strong adhesive. The outer flange of the flexible interface is connected to an opening in the center of the bottom wall or on the side wall of the high-pressure water tank, and the inner flange of the flexible interface is fixedly connected to the solid rocket engine under test, the latter being connected by a threaded connection. The reinforcements are made of high-strength alloys or reinforced resin-based composites. The elastic parts and reinforcements are alternately bonded together, making them more susceptible to shear deformation, further allowing the inner flange of the flexible interface and the solid rocket engine under test to achieve small axial displacement.

[0010] Preferably, the elastic member is made of natural rubber or silicone rubber.

[0011] The elastic members and the reinforcing members are alternately bonded together.

[0012] By ensuring that the solid rocket motor head matches the flexible interface inner flange, the thrust of solid rocket motors of different sizes can be tested.

[0013] The high-pressure water tank is filled with water and a certain amount of high-pressure gas is introduced to simulate the deep-water high-pressure environment of the solid rocket engine.

[0014] The sensor mounting stand is fastened to the sensor mounting stand rail of the high-pressure water tank by bolts. During installation, first adjust to the appropriate distance, then connect the high-precision tension and pressure sensor to the solid rocket engine under test and the sensor mounting stand, tighten the bolts, and fix the position of the sensor mounting stand.

[0015] After the test solid rocket engine is ignited, the high-temperature and high-speed gas jet is ejected backward, causing the test solid rocket engine to generate a certain thrust. Due to the use of flexible interfaces, the test solid rocket engine can move with a small displacement in the axial direction. Therefore, the thrust generated by the test solid rocket engine will be transmitted to the high-precision tensile and pressure sensor. The high-precision tensile and pressure sensor measures the axial thrust of the test solid rocket engine in a deep-water and high-pressure environment.

[0016] The installation method of a semi-submersible solid rocket engine deep-water thrust test device disclosed in the present invention is as follows:

[0017] There are two specific installation methods for the test solid rocket motor: one is vertical installation through an opening on the bottom wall of the high-pressure water tank, and the other is horizontal installation through an opening on the side wall of the high-pressure water tank. Due to the effects of gravity and buoyancy, when the test solid rocket motor is ignited underwater, the high-speed ejection of high-temperature combustion gas will form combustion bubbles, which will float upward due to gravity and buoyancy. Therefore, the thrust direction generated by the test solid rocket motor when installed horizontally will form a certain angle with the axial direction, resulting in axial thrust loss. By comparing the thrust difference of the test solid rocket motor under the vertical and horizontal installation conditions, the axial thrust loss of the test solid rocket motor when ignited horizontally in a deep-water high-pressure environment can be measured.

[0018] The invention discloses a semi-submerged solid rocket engine deep-water thrust test device, which can measure the thrust of the solid rocket engine in a deep-water high-pressure environment and the axial thrust loss generated during horizontal ignition.

[0019] The method for determining whether the material and size of elastic parts meet the design requirements is as follows:

[0020] The pressurization of the high-pressure water tank and the thrust of the solid rocket engine under test will form a shear force on the flexible interface. Under the action of the shear force, the flexible interface will produce a certain degree of axial deformation. The axial deformation of the flexible interface is μ, and the axial displacement of each layer of elastic parts is μ. n , then μ=∑μ n .

[0021] It is necessary to ensure that the shear stress on each layer of elastic member is less than the ultimate shear strength of the material used for the elastic member.

[0022] Regardless of whether the solid rocket engine under test is installed vertically or horizontally, the maximum axial deformation of the flexible interface occurs after the high-pressure water tank is pressurized. At this time, a stress analysis is performed on the solid rocket engine under test and the inner flange of the flexible interface as a whole, and the solid rocket engine under test and the inner flange of the flexible interface as a whole are named as the integral structure.

[0023] The overall structure is axisymmetric, and radial pressures cancel each other out. Therefore, only the axial forces are analyzed. The forces acting on the solid rocket motor under test differ somewhat when mounted vertically and horizontally, so these are analyzed separately.

[0024] After the high-pressure water tank is pressurized, the overall structure of the solid rocket engine under test is subjected to the axial force of gravity, internal and external pressure, and the elastic force of the elastic member on the inner flange of the flexible interface when it is installed vertically. The axial force balance yields:

[0025] F 外 +F 弹 =F 内 +G (1)

[0026] When the solid rocket motor under test is installed horizontally, the overall structure is subjected to internal and external pressure in the axial direction, as well as the elastic force of the elastic member on the inner flange of the flexible interface. The axial force balance yields:

[0027] F 外 +F 弹 =F 内 (2)

[0028] Where, F 外 F is the inward pressure exerted by the external atmospheric pressure on the entire structure. 弹 is the elastic force exerted by the flexible interface elastic member on the overall structure, F 内 is the outward pressure exerted by the internal water pressure on the overall structure, and G is the gravity exerted on the overall structure. The gravity G exerted on the overall structure consists of two parts: the gravity of the flange inside the flexible interface G 内法兰 and the solid rocket motor gravity G 发动机 , and have the following relationship:

[0029] G=G 内法兰 +G 发动机 (3)

[0030] From equations (1) and (2), it can be seen that the elastic part will bear greater shear force when the solid rocket engine under test is installed vertically. Therefore, when checking the strength of the elastic part, the vertical installation of the solid rocket engine under test is used as the verification standard.

[0031] The diameter of the inner flange of the flexible interface is Φ1, the diameter of the head of the solid rocket engine under test is Φ2, the diameter of the flange of the solid rocket engine under test is Φ3, the diameter of the main body of the solid rocket engine under test is Φ4, and the external atmospheric pressure of the high-pressure water tank is P 气 , the internal water pressure of the high pressure water tank is P 水 , and the internal and external pressures are evenly distributed on the surface of the entire structure, then the following relationship exists:

[0032]

[0033]

[0034] Substituting equations (4) and (5) into equation (1), we can further obtain:

[0035]

[0036] According to the principle of mutual force, the force on the flexible interface elastic part is related to F 弹 Equal in size and opposite in direction, denoted as F 弹 ′, then:

[0037] F 弹 ′=F 弹 (7)

[0038] The thickness of the elastic member is h1, the thickness of the reinforcement member is h2, and the width of both is l. The shear force on each layer of the elastic member is F 弹 ', but since the elastic parts closer to the outer layer have larger diameters and smaller shear stresses, the deformation of the innermost elastic parts is the largest, so only the strength of the innermost elastic parts needs to be checked to meet the strength requirements.

[0039] Since the thickness and width of the elastic parts and reinforcement parts are small, the stress is evenly distributed. The stress τ of the middle layer of the innermost elastic part is calculated as follows:

[0040]

[0041] Where A 弹1 is the equivalent area of ​​the middle layer of the innermost elastic member.

[0042] Substituting equations (3), (6) and (7) into equation (8), we can further obtain:

[0043]

[0044] Since h1 is much smaller than Φ1, Equation (9) can be further simplified as:

[0045]

[0046] Just make τ less than the shear stress limit τ of the elastic material max That is:

[0047] τ<τ max (11)

[0048] The material currently selected for the flexible interface elastic member and the dimensions of the elastic member, such as thickness h1 and width l, can meet the design requirements.

[0049] The present invention discloses a semi-submerged solid rocket engine deep-water thrust test device, which measures the thrust of the solid rocket engine in a deep-water high-pressure environment and the axial thrust loss generated during horizontal ignition, including the following steps:

[0050] Step 1: Measure the thrust of the solid rocket motor in a deep-water high-pressure environment;

[0051] The solid rocket motor under test is vertically mounted on the central opening of the bottom wall of the high-pressure water tank through a flexible interface. The high-pressure water tank is then filled with water and a certain amount of high-pressure gas to simulate the deep-water high-pressure environment.

[0052] Install the sensor mounting stand and connect the solid rocket motor to the sensor mounting stand using high-precision tension and pressure sensors;

[0053] The solid rocket motor under test ignites and generates thrust. Due to the use of a flexible interface, the thrust generated by the solid rocket motor under test is transmitted to the high-precision tension and pressure sensor. The high-precision tension and pressure sensor measures the thrust of the solid rocket motor under test in a deep-water high-pressure environment.

[0054] Step 2: Measure the axial thrust loss generated when the solid rocket motor is horizontally ignited in a deep water high pressure environment;

[0055] The solid rocket motor to be tested is installed horizontally on the opening at the lower position of the side wall of the high-pressure water tank through a flexible interface. Then the high-pressure water tank is filled with water and a certain amount of high-pressure gas is introduced to simulate the deep-water high-pressure environment.

[0056] Install the sensor mounting stand and connect the solid rocket motor to the sensor mounting stand using high-precision tension and pressure sensors;

[0057] The solid rocket motor under test ignites and generates thrust. Due to the use of a flexible interface, the thrust generated by the solid rocket motor under test is transmitted to the high-precision tension and pressure sensor. The high-precision tension and pressure sensor measures the axial thrust of the solid rocket motor under test in a deep-water high-pressure environment.

[0058] Due to the effects of gravity and buoyancy, the high-speed, high-temperature combustion gas ejected from the solid rocket engine under test will form gas bubbles and float upward due to the effects of gravity and buoyancy. Therefore, when the solid rocket engine under test is installed horizontally, the thrust direction generated will form a certain angle with the axial direction, resulting in axial thrust loss.

[0059] Since the test solid rocket engine will not produce thrust loss when installed vertically, by comparing the thrust difference when the test solid rocket engine is installed horizontally and vertically, the axial thrust loss generated by the test solid rocket engine when ignited horizontally in a deep water high-pressure environment can be measured.

[0060] Beneficial effects:

[0061] 1. Compared with traditional solid rocket engine thrust tests, the semi-submerged solid rocket engine deep-water thrust test device disclosed in the present invention can ensure that the solid rocket engine under test operates in a simulated deep-water environment, while at the same time allowing the test equipment and ignition cables to be in a normal-pressure atmospheric environment. There is no need for strict waterproofing treatment of the equipment, which significantly simplifies the test process and avoids test failures caused by waterproofing failure of the equipment.

[0062] 2. The present invention discloses a semi-submerged solid rocket engine deep-water thrust test device, which can perform thrust tests on both vertically installed engines and horizontally installed engines, thereby calculating the axial thrust loss generated by a horizontally ignited solid rocket engine in a deep-water high-pressure environment.

[0063] 3. The semi-submerged solid rocket engine deep-water thrust test device disclosed in the present invention can test the thrust of solid rocket engines of different sizes by simply matching the head of the solid rocket engine under test with the inner flange of the flexible interface. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 This is a front view of the semi-submerged solid rocket motor deep-water thrust test device (the solid rocket motor under test is installed vertically);

[0065] Figure 2 This is a side view of the semi-submerged solid rocket motor deep-water thrust test device (the solid rocket motor under test is installed vertically);

[0066] Figure 3 This is a top view of the semi-submerged solid rocket motor deep-water thrust test device (the solid rocket motor under test is installed vertically);

[0067] Figure 4 This is a diagram of the flexible interface structure of the semi-submerged solid rocket motor deep-water thrust test device;

[0068] Figure 5 This is a schematic diagram of the axial force of the solid rocket motor under test and the flexible interface inner flange of the semi-submerged solid rocket motor deep-water thrust test device (the solid rocket motor under test is installed vertically);

[0069] Figure 6 This is a schematic diagram of the force and deformation of the flexible interface elastic parts of this semi-submerged solid rocket engine deep-water thrust test device.

[0070] Among them, 1—water tank body; 2—water tank top cover; 3—flexible interface; 4—sealing plug; 5—observation window; 6—sensor mounting stand guide rail; 7—high-precision tension and pressure sensor; 8—sensor mounting stand; 9—water inlet; 10—air inlet; 11—exhaust port; 12—cable opening; 13—drain port; 14—solid rocket engine body; 15—solid rocket engine head; 2-1—flexible interface outer flange; 2-2—flexible interface inner flange; 2-3—elastic part; 2-4—reinforcement part. DETAILED DESCRIPTION

[0071] In order to better illustrate the purpose and advantages of the present invention, the invention is further described below in conjunction with the accompanying drawings.

[0072] The purpose of the present invention is to measure the deep-water thrust of a solid rocket engine under the premise that the test equipment and the ignition cable are in a normal pressure atmospheric environment and do not require strict waterproofing treatment, and further measure the axial thrust loss of the solid rocket engine during horizontal ignition in a deep-water high-pressure environment.

[0073] like Figures 1 to 3 As shown, this example discloses a semi-submerged solid rocket engine deep-water thrust test device, which is designed to simulate a 300m water depth environment and consists of a high-pressure water tank, a flexible interface 3, a test solid rocket engine, a high-precision tension and pressure sensor 7 and a sensor mounting stand 8, as shown in the figure.

[0074] The high-pressure water tank consists of a main body 1, a top cover 2, and a sensor mounting platform rail 6. The top cover 2 includes a water inlet 9, an air inlet 10, an exhaust port 11, and a cable opening 12. The main body 1 also has an opening in the center of its bottom wall and a lower opening on its side wall for connecting to a flexible interface 3. The side wall of the main body 1 includes an observation window 5, and a drain outlet 13 is located along the edge of its bottom wall.

[0075] The solid rocket engine under test is composed of a solid rocket engine head 15 and a solid rocket engine body 14 that match the flexible interface 3. The total weight of the solid rocket engine under test is G 发动机 It is 56.0561N.

[0076] like Figure 4 As shown, the flexible interface 3 is composed of a flexible interface outer flange 2-1, a flexible interface inner flange 2-2, and four layers of elastic members 2-3 and four layers of reinforcement members 2-4 located therebetween. The four are bonded together by a strong adhesive. The diameter Φ1 of the flexible interface inner flange 2-2 is 62 mm, the thickness h1 of the elastic member 2-3 is 3 mm, the thickness h2 of the reinforcement member 2-4 is 2 mm, the width l of the elastic member 2-3 and the reinforcement member 2-4 are both 15 mm, and the gravity G of the flexible interface inner flange 2-2 is 0. 内法兰 The material used for the elastic member 2-3 is artificial rubber, and its shear stress limit τ max It is 40~70MPa.

[0077] The shear stress limit of the flexible interface elastic member 2-3 is checked, and the above formulas (8) and (9) are applied to obtain:

[0078]

[0079] Therefore, the material selected for the current flexible interface elastic member 2-3 and the dimensions of the elastic member such as thickness and width can meet the design requirements.

[0080] Step 1: Measure the thrust of the solid rocket motor at a water depth of 300m:

[0081] The flexible interface 3 is connected to the opening on the bottom wall of the high-pressure water tank through a flange, and the opening on the side wall of the high-pressure water tank is sealed by a sealing plug 4.

[0082] Open the top cover 2 of the high-pressure water tank, and install the solid rocket engine to be tested on the flexible interface 3 through the inside of the water tank. The two are connected by threads. The radial and torsional movement of the solid rocket engine to be tested is restricted by the stand located inside the high-pressure water tank.

[0083] Install the water tank cover 2.

[0084] Close the drain port 13 at the bottom of the water tank, open the water inlet 9 on the top cover of the water tank, start water intake, wait until the water intake reaches about 4 / 5 of the water tank volume, stop water intake, and close the water inlet 9.

[0085] A pressure sensor is installed inside the tank's top cover 2 and is connected to pressure monitoring equipment outside the tank via a cable opening 12 on the top cover 2. The air inlet 10 on the tank's top cover 2 is opened and high-pressure gas is introduced. When the pressure inside the tank reaches the designed water depth, the air intake is stopped and the air inlet 10 is closed.

[0086] The high-precision tension and pressure sensor 7 is connected to the solid rocket engine head 15 under test, and is connected to the external thrust monitoring equipment through a cable.

[0087] Slowly push the sensor mounting bracket 8 into the sensor mounting bracket rail 6 and connect the high-precision tension and pressure sensor 7. Apply a certain preload force to the sensor mounting bracket 8 until the external thrust monitoring device detects a slightly lower value. Immediately use bolts to fix the sensor mounting bracket 8 to the sensor mounting bracket rail 6.

[0088] The monitoring value of the high-precision tension and pressure sensor 7 is reset to zero.

[0089] Since the solid rocket engine will eject a large amount of gas after ignition, which will further increase the pressure in the water tank, the pressure sensor located on the water tank top cover 2 is monitored in real time. When the pressure in the water tank is higher than the design value, the exhaust port 11 is opened and the air inlet is closed to exhaust. When the pressure in the water tank is lower than the design value, the exhaust port 11 is closed and the air inlet 10 is opened to intake air to ensure that the pressure in the water tank is always maintained at the design value.

[0090] At this point, the entire semi-submerged solid rocket engine deep-water thrust test device (the solid rocket engine under test is installed vertically) has been completed.

[0091] After the solid rocket engine under test is ignited, thrust is generated. The high-precision tensile and pressure sensor 7 is squeezed by the thrust and transmits the thrust value information back to the external thrust monitoring equipment in real time, measuring the thrust of the solid rocket engine under test in a water depth of 300m.

[0092] Step 2: Measure the axial thrust loss generated by the solid rocket motor when it is horizontally ignited at a water depth of 300m:

[0093] The flexible interface 3 is connected to the opening on the side wall of the high-pressure water tank through a flange, and the opening on the bottom wall of the high-pressure water tank is sealed by a sealing plug 4.

[0094] Open the top cover 2 of the high-pressure water tank, and install the solid rocket engine to be tested on the flexible interface 3 through the inside of the water tank. The two are connected by threads. The radial and torsional movement of the solid rocket engine to be tested is restricted by the stand located inside the high-pressure water tank.

[0095] Install the water tank cover 2.

[0096] Close the drain port 13 at the bottom of the water tank, open the water inlet 9 on the top cover of the water tank, start water intake, wait until the water intake reaches about 4 / 5 of the water tank volume, stop water intake, and close the water inlet 9.

[0097] A pressure sensor is installed inside the tank's top cover 2 and is connected to pressure monitoring equipment outside the tank via a cable opening 12 on the top cover 2. The air inlet 10 on the tank's top cover 2 is opened and high-pressure gas is introduced. When the pressure inside the tank reaches the designed water depth, the air intake is stopped and the air inlet 10 is closed.

[0098] The high-precision tension and pressure sensor 7 is connected to the solid rocket engine head 15 under test, and is connected to the external thrust monitoring equipment through a cable.

[0099] Slowly push the sensor mounting bracket 8 into the sensor mounting bracket rail 6 and connect the high-precision tension and pressure sensor 7. Apply a certain preload force to the sensor mounting bracket 8 until the external thrust monitoring device detects a slightly lower value. Immediately use bolts to fix the sensor mounting bracket 8 to the sensor mounting bracket rail 6.

[0100] The monitoring value of the high-precision tension and pressure sensor 7 is reset to zero.

[0101] Since the solid rocket engine will eject a large amount of gas after ignition, which will further increase the pressure in the water tank, the pressure sensor located on the water tank top cover 2 is monitored in real time. When the pressure in the water tank is higher than the design value, the exhaust port 11 is opened and the air inlet is closed to exhaust. When the pressure in the water tank is lower than the design value, the exhaust port 11 is closed and the air inlet 10 is opened to intake air to ensure that the pressure in the water tank is always maintained at the design value.

[0102] At this point, the entire semi-submerged solid rocket engine deep-water thrust test device (the solid rocket engine under test is installed horizontally) has been completed.

[0103] After the solid rocket engine under test is ignited, thrust is generated. The high-precision tensile and pressure sensor 7 is squeezed by the thrust and transmits the thrust value information back to the external thrust monitoring equipment in real time. The thrust of the solid rocket engine under test during horizontal ignition in a water depth of 300m is measured.

[0104] By comparing the thrust differences when the solid rocket motor was installed horizontally and vertically, the axial thrust loss generated by the horizontal ignition of the solid rocket motor in a water depth of 300m was measured.

[0105] By using the flexible interface 3, the solid rocket engine under test can operate in a simulated deep-water environment, while various test equipment such as the high-precision tension and pressure sensor 7 and the ignition cable are placed in a normal pressure atmospheric environment without the need for waterproofing, which significantly simplifies the test process and can further avoid test failures caused by equipment waterproofing failure.

[0106] The above specific description further illustrates the purpose, technical solutions and beneficial effects of the invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A semi-submersible solid rocket engine deep-water thrust test device, characterized by: It is mainly composed of a high-pressure water tank, a flexible interface, a solid rocket engine to be tested, a high-precision tension and pressure sensor, and a sensor mounting stand; The high-pressure water tank consists of three parts: the tank body, the tank cover, and the sensor mounting platform guide rail. The tank cover and the tank body are connected by a flange, and the sensor mounting platform guide rail is fixedly connected to the tank body. The tank cover has a water inlet, an air inlet, an exhaust port, and a cable opening. The tank body has an opening in the center of the bottom wall and at the lower part of the side wall for connecting to the flexible interface. The side wall of the tank body also has an observation window, and the edge of the bottom wall has a drain port. The solid rocket motor under test consists of a solid rocket motor head and a solid rocket motor body, which are fixedly connected by a flange; The flexible interface consists of inner and outer flanges and several elastic parts and reinforcement parts located between the two. The inner flange, outer flange, elastic parts and reinforcement parts are fixedly connected. The outer flange of the flexible interface is connected to the central position of the bottom wall or the opening on the side wall of the high-pressure water tank, and the inner flange of the flexible interface is fixedly connected to the head of the solid rocket being tested. The combination of the elastic parts and reinforcement parts will undergo shear deformation, so that the inner flange of the flexible interface and the solid rocket engine being tested connected thereto can achieve small displacement axial movement, further allowing the thrust of the solid rocket engine being tested to be transmitted to the high-precision tension and pressure sensor. The sensor mounting platform is fixedly installed on the sensor mounting platform rail of the high-pressure water tank; the high-precision tension and pressure sensor is connected to the head of the solid rocket engine under test and the sensor mounting platform, and is connected to the external thrust monitoring equipment through cables; By comparing the thrust differences when the solid rocket motor was installed horizontally and vertically, the axial thrust loss generated by the solid rocket motor when it was horizontally ignited in a deep-water high-pressure environment was measured.

2. A semi-submersible solid rocket engine deep-water thrust test device as claimed in claim 1, characterized in that: The method for determining whether the material and size of elastic parts meet the design requirements is as follows: During the test, the flexible interface will be subjected to shear force, which includes the pressure generated by the pressure difference between the inside and outside of the high-pressure water tank and the thrust generated by the ignition of the solid rocket engine under test. When the solid rocket engine under test is installed vertically, the shear force will also include the gravity of the solid rocket engine under test. Under the action of the shear force, the flexible interface will produce a certain degree of axial deformation. The axial deformation of the flexible interface is μ, and the axial displacement of each layer of elastic parts is μ. n , μ=∑μ n ; It is necessary to ensure that the shear stress on each layer of elastic parts is less than the ultimate shear strength of the material used for the elastic parts; Regardless of whether the solid rocket motor under test is installed vertically or horizontally, the maximum axial deformation of the flexible interface occurs after the high-pressure water tank is pressurized. At this time, a force analysis is performed on the solid rocket motor under test and the inner flange of the flexible interface as a whole. The solid rocket motor under test and the inner flange of the flexible interface as a whole are named as the integral structure; The overall structure is axisymmetric, and the radial pressures cancel each other out; After the high-pressure water tank is pressurized, the overall structure of the solid rocket engine under test is subjected to the axial force of gravity, internal and external pressure, and the elastic force of the elastic member on the inner flange of the flexible interface when it is installed vertically. The axial force balance yields: F 外 +F 弹 =F 内 +G (1) When the solid rocket motor under test is installed horizontally, the overall structure is subjected to internal and external pressure in the axial direction, as well as the elastic force of the elastic member on the inner flange of the flexible interface. The axial force balance yields: F 外 +F 弹 =F 内 (2) Where, F 外 F is the inward pressure exerted by the external atmospheric pressure on the entire structure. 弹 is the elastic force exerted by the flexible interface elastic member on the overall structure, F 内 is the outward pressure exerted by the internal water pressure on the entire structure, and G is the gravity exerted on the entire structure; The gravity G on the whole structure consists of two parts: the gravity G of the flange inside the flexible interface 内法兰 and the solid rocket motor gravity G 发动机 , and have the following relationship: G=G 内法兰 +G 发动机 (3) From equations (1) and (2), it is known that the elastic part will bear greater shear force when the solid rocket engine under test is installed vertically. Therefore, when checking the strength of the elastic part, the vertical installation of the solid rocket engine under test is used as the checking standard. The diameter of the inner flange of the flexible interface is Φ1, the diameter of the head of the solid rocket engine under test is Φ2, the diameter of the flange of the solid rocket engine under test is Φ3, the diameter of the main body of the solid rocket engine under test is Φ4, and the external atmospheric pressure of the high-pressure water tank is P 气 , the internal water pressure of the high pressure water tank is P 水 , and the internal and external pressures are evenly distributed on the surface of the entire structure, then the following relationship exists: Substituting equations (4) and (5) into equation (1), we can further obtain: According to the principle of mutual force, the force on the flexible interface elastic part is related to F 弹 Equal in size and opposite in direction, denoted as F 弹 ′, then: F 弹 ′=F 弹 (7) The thickness of the elastic member is h1, the thickness of the reinforcement member is h2, and the width of both is l; the shear force on each layer of the elastic member is F 弹 ', but because the elastic member closer to the outer layer has a larger diameter and is subjected to a smaller shear stress, the innermost elastic member has the largest deformation and is subjected to the largest shear stress; Since the thickness and width of the elastic parts and reinforcement parts are small, the stress is evenly distributed. The stress τ of the middle layer of the innermost elastic part is calculated as follows: Where A 弹1 is the equivalent area of ​​the middle layer of the innermost elastic member; Substituting equations (3), (6) and (7) into equation (8), we can further obtain: Since h1 is much smaller than Φ1, Equation (9) can be further simplified as follows: Let τ be less than the shear stress limit τ of the elastic material max ,Right now: τ<τ max (11) The material currently selected for the flexible interface elastic member and the dimensions of the elastic member, such as thickness h1 and width l, can meet the design requirements.

3. The semi-submersible solid rocket engine deep-water thrust test device according to claim 1, characterized in that: The material of the elastic member includes natural rubber and silicone rubber; the material of the reinforcing member includes high-strength alloy and reinforced resin-based composite material; the elastic member and the reinforcing member are alternately bonded together.

4. The semi-submersible solid rocket engine deep-water thrust test device according to claim 1, characterized in that: The solid rocket engine under test consists of a solid rocket engine head that matches the inner flange of the flexible interface and a solid rocket engine body. The radial and torsional movements of the solid rocket engine under test are restricted by a stand located inside the high-pressure water tank.

5. A method for testing using the device according to any one of claims 1 to 4, characterized in that: Measuring the thrust of a solid rocket motor in a deep-water, high-pressure environment and the axial thrust loss during horizontal firing includes the following steps: Step 1: Measure the thrust of the solid rocket motor in a deep-water high-pressure environment; The solid rocket motor under test is vertically mounted on the central opening of the bottom wall of the high-pressure water tank through a flexible interface. The high-pressure water tank is then filled with water and a certain amount of high-pressure gas to simulate the deep-water high-pressure environment. Install the sensor mounting stand and connect the solid rocket motor to the sensor mounting stand using high-precision tension and pressure sensors; The solid rocket motor under test ignites and generates thrust. Due to the use of a flexible interface, the thrust generated by the solid rocket motor under test is transmitted to the high-precision tension and pressure sensor. The high-precision tension and pressure sensor measures the thrust of the solid rocket motor under test in a deep-water high-pressure environment. Step 2: Measure the axial thrust loss generated when the solid rocket motor is horizontally ignited in a deep water high pressure environment; The solid rocket motor to be tested is installed horizontally on the opening at the lower position of the side wall of the high-pressure water tank through a flexible interface. Then the high-pressure water tank is filled with water and a certain amount of high-pressure gas is introduced to simulate the deep-water high-pressure environment. Install the sensor mounting stand and connect the solid rocket motor to the sensor mounting stand using high-precision tension and pressure sensors; The solid rocket motor under test ignites and generates thrust. Due to the use of a flexible interface, the thrust generated by the solid rocket motor under test is transmitted to the high-precision tension and pressure sensor. The high-precision tension and pressure sensor measures the axial thrust of the solid rocket motor under test in a deep-water high-pressure environment. Due to the effects of gravity and buoyancy, the high-speed, high-temperature combustion gas ejected from the solid rocket engine under test will form gas bubbles and float upward due to the effects of gravity and buoyancy. Therefore, when the solid rocket engine under test is installed horizontally, the thrust direction generated will form a certain angle with the axial direction, resulting in axial thrust loss. Since the solid rocket engine under test will not produce thrust loss when installed vertically, by comparing the thrust difference when the solid rocket engine under test is installed horizontally and vertically, the axial thrust loss generated by the solid rocket engine under test when ignited horizontally in a deep water high-pressure environment can be measured.

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