Submarine damage model device for carrying out large-water-depth underwater explosion in limited water area and test method

Abstract

The invention discloses a submarine damage model device for carrying out large-water-depth underwater explosion in a limited water area and a test method, and belongs to the field of model tests. The model device comprises a pool, a testing device, a free field pressure sensor and an explosion source, the testing device is arranged in the water tank, and an explosion source fixed by an explosion source positioning rod is arranged on one side of the testing device; the testing device comprises an anti-impact buoy and a submarine target, and the anti-impact buoy suspends the submarine target in a pool through a load-bearing steel wire rope and is located on the surface of the pool. Ballast connected through a load-bearing steel wire rope is arranged at the bottom of the submarine target. Free field pressure sensors which are connected with the anti-impact buoy through a free sensor laying device are arranged around the testing device. The problem that the submarine structure is impacted and damaged by the load under the action of deepwater explosion impact is solved, and the device can be repeatedly used, is easy to control and convenient to disassemble, and reduces the experiment cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of model test, and particularly relates to a model device for submarine damage test caused by underwater explosion in a limited water area and a test method. BACKGROUND

[0002] Improving the anti-explosion and anti-impact performance and survivability of surface ships and underwater submarines is an important prerequisite for ensuring their functions, and the research on this problem has attracted widespread attention. A large amount of valuable data has been accumulated through many real-ship explosion experiments, while underwater explosion experiments are relatively less carried out in China, especially explosion experiments on underwater submarines are rare, which to some extent limits the improvement of the anti-explosion and anti-impact design capability of ships and submarines.

[0003] In conventional explosion water tanks and explosion tanks, the effect of deep water explosion near an actual submarine is simulated. Since the volume and strength of the explosion water tank and the explosion tank are limited, the amount of experimentable explosive is limited, and the volume is limited. The shock wave will be reflected inside the container, which does not match the actual situation and will interfere with the experimental data. In order to overcome this deficiency, the existing experimental method is carried out in an explosion water pool. However, it is difficult to carry out a large water depth experiment in an explosion water pool. Due to the problem of target model scale, it will cause actual problems such as being unable to operate. Therefore, it is necessary to propose a test method for submarine damage model caused by underwater explosion in a limited water area. SUMMARY

[0004] The present application provides an explosion submarine damage model device for simulating submarine damage test caused by large water depth underwater explosion, which can simulate the impact force received by the prototype explosion.

[0005] The present application provides an explosion submarine damage model device for simulating submarine damage test caused by large water depth underwater explosion, which can simulate the impact force received by the prototype explosion. The explosion submarine damage model device for simulating submarine damage test caused by large water depth underwater explosion comprises a water pool, a test device, a free-field pressure sensor, and an explosion source. The test device is arranged inside the water pool, and the explosion source is fixed on one side of the test device through an explosion source positioning rod. The test device comprises an anti-impact float and a submarine target. The submarine target is suspended in the water pool by the anti-impact float through a load-bearing steel wire rope, and the anti-impact float is located on the surface of the water pool. The bottom of the submarine target is provided with a ballast connected by the load-bearing steel wire rope. The free-field pressure sensor is connected to the anti-impact float through an adjustable free sensor laying device around the test device. The radius of the explosion source, the mass of the explosion source, and the distance between the explosion source and the test device meet the test requirements of the scaled test device.

[0006] Further, the anti-impact float comprises a single cylinder. A plurality of single cylinders are connected through a transverse stabilizing plate. The single cylinder is a cylindrical cover plate with uniformly arranged ring ribs inside. A T-shaped beam reinforcing rib is arranged on the inner wall of the cylindrical cover plate. A watertight door is arranged on the submarine target.

[0007] Furthermore, the distance between the submarine target and the explosion source is designed based on an equal impact factor:

[0008]

[0009] Among them, W p The amount of explosive charge used in the prototype test; R p For prototype test detonation distance; W p The amount of explosive charge for submarine target testing; R m The test range for submarine target blasting;

[0010]

[0011] Where D is the maximum diameter of the bubble; H is the water depth of the prototype test; H0 is the prototype atmospheric pressure head; J w These are empirical constants related to the properties of explosives;

[0012] Furthermore, the radius of the submarine target section is designed based on the spherical wave effect:

[0013]

[0014] Where, r m r is the radius of the submarine target section. p The radius of the prototype module;

[0015] The obtained submarine target section radius r m With the prototype section radius r p The ratio is used to determine the geometric scaling factor of the submarine target size.

[0016] Furthermore, the axial length L of the submarine target needs to satisfy the critical angle constraint condition for shock wave incidence:

[0017]

[0018] Among them, C w C is the speed at which a transverse wave propagates in water. s Let be the propagation speed of the transverse wave in the steel.

[0019] Furthermore, the explosion source depth l is based on the submarine target radius r. 靶标半径 and the axial length L of the impact-resistant pontoon 抗冲击浮筒 Design it:

[0020]

[0021] Furthermore, the load-bearing steel wire rope is connected to the lower lifting lug at the bottom of the impact-resistant buoy and the upper lifting lug at the top of the submarine target, and the length J of the load-bearing steel wire rope is:

[0022]

[0023] Wherein, P is the transverse distance between the upper and lower hangers; W is the distance between the submarine target and the impact-resistant buoy;

[0024] H = h - d - G

[0025]

[0026] d = r1 - L1

[0027] Wherein, h is the test water depth; d is the draft of the impact-resistant buoy; G is the axial length between the center point of the submarine target and the hanger; β is the angle between the center point of the submarine target and the hanger; r1 is the radius of the impact-resistant buoy; L1 is the distance between the center of the impact-resistant buoy and the water surface of the test pool.

[0028] Further, the actual displacement F of the impact-resistant buoy 浮筒实际的排水量 According to the submarine mass G 模型质量 , the ballast mass G 压载质量 , the impact-resistant buoy mass G 浮筒质量 , the submarine mass displacement F 模型排水量 , the ballast displacement F 压载排水量 , the design is:

[0029] F 浮筒实际的排水量 +F 模型排水量 +F 压载排水量 =G 浮筒质量 =G 模型质量 +G 压载质量

[0030] The draft area of the impact-resistant buoy is calculated according to the ratio of the actual displacement to the total displacement, and then the non-draft area is calculated by the total area of the impact-resistant buoy, so as to calculate the distance between the center of the impact-resistant buoy and the water surface of the test pool;

[0031]

[0032] L1 = r1cos a

[0033] Wherein, S1 is the non-draft area of the impact-resistant buoy; S2 is the draft area of the impact-resistant buoy; a is the central angle of the non-draft area.

[0034] Further, the distance R between the underwater free-field sensor and the explosion center of the explosive source, and the radius r2 of the explosive source are designed according to the peak pressure P m required by the test, satisfying the following relationship:

[0035]

[0036] Wherein, l1, k1 are test coefficients; α1, β1 are impact pressure attenuation coefficients.

[0037] This invention also provides a test method for conducting a test on a submarine damage model device at great depths in a limited water area, comprising the following steps:

[0038] Step 1: Select submarine targets of different sizes according to the test requirements. Personnel enter the target through the watertight hatch to deploy sensors. After deployment, close the hatch and check its watertightness. The sensors include an impact acceleration sensor, a wall pressure sensor, and strain gauges. The impact acceleration sensor is threaded onto the metal base of the submarine target, and the metal base is then welded to the measurement position inside the model. The wall pressure sensor is threaded into a through-hole in the model's outer shell, with the measuring head tangent to the model's toroidal surface, and the installation position is kept watertight. The strain gauge attachment position is polished with a grinding wheel to a metallic luster, and then adhered to the measurement position using strain gauge adhesive.

[0039] Step 2: Connect the lower lifting lug of the impact-resistant pontoon to the upper lifting lug of the submarine target using a load-bearing steel wire rope. Connect the lower lifting lug of the target to the ballast using a steel wire rope.

[0040] Step 3: Adjust the length of the load-bearing steel wire rope between the impact-resistant pontoon and the submarine target according to the target parameters, float the impact-resistant pontoon on the water surface, and put the submarine target into the water;

[0041] Step 4: Place the pre-installed free field sensor connecting rod on the water surface, adjust it to the correct position, and let the free field sensor with the connecting wire fall freely into the water to a certain depth to observe the stability of its measurement channel.

[0042] Step 5: The blast source is connected to the connecting rod on the pontoon via a thin line and is lowered freely to a certain depth, with the lower end of the blast source bearing a ballast load;

[0043] Step 6: Check the test cable. If there are no problems, start the test; test the explosion response at different distances.

[0044] The beneficial effects of this invention are as follows:

[0045] The experimental device of this invention is reusable. Its high-strength, impact-resistant pontoons minimize the impact of underwater explosions. Even after the submarine target is destroyed by the explosion and water enters, causing it to lose buoyancy, the pontoons provide sufficient positive buoyancy to prevent the experimental device from sinking. The target can be retrieved and replaced with another target for further experimentation. This invention's experimental device, through scaled-down simulation of a prototype, can perform underwater explosion damage model tests on submarines at great depths, ensuring that the impact force on the experimental device is equivalent to the force experienced by the prototype after the explosion. Furthermore, the impact-resistant pontoons provide the necessary buoyancy and stability for the experiment, and the test personnel only need to work on the surface ferry and the impact-resistant pontoons, eliminating the need for diving, thus facilitating the deployment and retrieval of the model. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the experimental setup of the present invention in an explosion water tank.

[0047] Figure 2 This is a schematic diagram of the connection and assembly of the test device of the present invention;

[0048] Figure 3 This is a physical diagram of the test site layout of the sample apparatus of the present invention;

[0049] Figure 4 This is a schematic diagram of the impact-resistant pontoon of the test device of the present invention;

[0050] Figure 5 This is a schematic diagram of the spherical wave effect of the experimental device of the present invention;

[0051] Figure 6 This is a schematic diagram of the reflection of a plane longitudinal wave on a free boundary using the experimental device of the present invention;

[0052] Figure 7 This is a schematic diagram of the axial dimensions of the submarine target model of the experimental device of the present invention.

[0053] Figure 8 This is a schematic diagram of the draft of the impact-resistant float of the test device of the present invention;

[0054] Figure 9 This is a schematic diagram of the load-bearing steel cable of the test device of the present invention.

[0055] The attached diagram is labeled as follows: 1-Roadbed; 2-Crane truck; 3-Explosion source; 4-Target and impact-resistant pontoon; 4-1-Impact-resistant pontoon; 4-1-1-Impact-resistant pontoon single tube; 4-1-2-Impact-resistant pontoon upper lifting lug; 4-1-3-Double-through connecting frame; 4-14-Cover plate; 4-1-5-Large ring rib plate; 4-1-6-Reinforcing T-profile; 4-2-Target; 5-Free field sensor; 6-Deep water area of ​​the explosion pool; 7-Edge of the explosion pool; 8-Test room; 9-Test cable; 10-Load-bearing steel wire rope; 11-Explosion source positioning rod; 12-Adjustable free field sensor deployment device; 13-Ballast; 14-Thin rope. Detailed Implementation

[0056] The present invention will now be further described with reference to the accompanying drawings.

[0057] A test device for conducting underwater explosion damage model tests on submarines in confined waters at great depths, such as... Figures 1-4 As shown, it includes a water tank, a testing device, a free-field pressure sensor, and an explosion source;

[0058] The testing device is arranged inside a water tank, with a blast source fixed to one side by a blast source positioning rod. The testing device includes an impact-resistant buoy and a submarine target. The impact-resistant buoy suspends the submarine target inside the water tank via a load-bearing steel cable, and the impact-resistant buoy is located on the surface of the water tank. A ballast connected to the bottom of the submarine target via a load-bearing steel cable is arranged. Free-field pressure sensors connected to the impact-resistant buoy via an adjustable free sensor deployment device are arranged around the testing device. The radius, mass, and distance of the blast source from the testing device meet the test requirements of the scaled-down testing device.

[0059] The impact-resistant buoy includes a single tube, and multiple single tubes are connected by a transverse stabilizing plate. The single tube is a cylindrical cover plate with evenly arranged ring ribs inside, and the inner wall of the cylindrical cover plate is provided with T-shaped beam reinforcing ribs. The impact-resistant buoy has a very large positive buoyancy, which can be used to lift large-scale submarine targets through load-bearing steel cables. Even after the large-sized target loses buoyancy, it will not sink into the water and can be salvaged.

[0060] The impact-resistant pontoon consists of two single-tube pontoons connected laterally by a transverse stabilizing plate. Internally reinforced with T-shaped profiles, it maintains a certain distance from the underwater blast source, minimizing the impact of continuous explosions. The target has a watertight hatch, allowing personnel access and operation. Each pontoon is equipped with four lifting lugs; the upper lug connects to a truck crane, and the lower lug connects to a load-bearing steel wire rope. A free-field pressure sensor positioning rod is connected to the impact-resistant pontoon's connecting frame. The rod carries a free-field pressure sensor with test leads, allowing it to be lowered to a specified underwater depth to measure the shock wave pressure generated by the blast source. The load-bearing steel wire rope is selected with a relatively thin diameter to minimize the impact of a sudden explosion on the pontoon.

[0061] (1) Scaled-down design of a model considering the spherical wave effect of shock waves (contact explosion)

[0062] The spherical wave effect of the model must be consistent with that of the prototype, meaning the model input conditions are the same. The ratio of the burst distance to the radius of the bubble in a free-field underwater explosion is used as the criterion parameter; a contact explosion occurs when the burst distance equals the bubble radius. When a contact explosion occurs on the prototype, the burst distance for the model test is designed based on the equal impact factor, and the model diameter is designed by combining the spherical wave effects of the prototype and model. Then, the geometric scaling factor of the model size is determined based on the ratio of the model diameter to the prototype diameter. The maximum diameter of the bubble is:

[0063]

[0064] Where W is the explosive charge quantity in kg; H is the test water depth in m; H is the atmospheric pressure head in m; J w These are empirical constants related to the properties of explosives.

[0065] At this point, the maximum radius D / 2 of the bubble is set as the prototype test burst distance R.p The impact factor C of the prototype test was calculated sequentially as follows:

[0066]

[0067] Based on the fact that the impact factor C of the prototype and the model are equal:

[0068] C m =C p

[0069] Among them, C m For model test impact factor; C p The impact factor is used in model experiments.

[0070] The calculated blast distance R under the model working condition was obtained. m The radius of the model compartment was calculated based on the ratio of the wavefront to the section radius during the contact explosion of the prototype, as shown below. Figure 5 The diagram shown is a schematic of the spherical wave effect.

[0071]

[0072] Where, r m r is the radius of the submarine target section. p The radius of the prototype module;

[0073] The model diameter is obtained by combining the spherical wave effect of the prototype and the model. Then, the geometric scaling factor of the model size is determined based on the ratio of the model diameter to the prototype diameter.

[0074] The prototype operates at a water depth of 100m and uses 250kg of TNT. When a contact explosion occurs, the explosion distance R under these conditions is calculated using the formula for the maximum radius of the air bubble. p =6.4m, at which point the impact factor C is 0.97. When the model charge mass is 0.5kg, the calculated detonation distance for the model under working conditions is 0.81m. Due to the ratio of the wavefront to the section diameter when the prototype experiences a contact explosion, the prototype section diameter is 13m, and the calculated model section diameter is 1.64m. At this point, the model scaling ratio is 1:8, and the section model is designed on a scale based on this scaling ratio.

[0075] (2) Design of axial dimensions of the model considering the critical incident angle of the shock wave

[0076] In similar model tests, an increase in the scale ratio leads to a decrease in the explosion distance, which in turn enhances the spherical effect of the shock wave and causes a sudden change in the wall pressure on the model wall. Therefore, it is necessary to investigate the critical angle at which the incident shock wave changes abruptly, and limit the axial length of the model based on the oblique incident angle to ensure that the incident load of the model is similar to that of the prototype.

[0077] When an elastic plane wave is incident obliquely on a free surface, such asFigure 6 As shown, tilted reflection occurs on the free surface. The boundary conditions are that the orthogonal stress and shear stress on the free surface are zero, but the tangential stress is not necessarily zero. When the incident wave is a plane longitudinal wave, two types of waves may be generated during reflection: a reflected longitudinal wave and a reflected shear wave.

[0078] The angle between the reflected longitudinal wave and the normal to the free plane is equal to the angle between the incident wave and the normal, but the angle between the reflected shear wave and the normal is different, which can be proven (similar to Fresnel's law for light):

[0079]

[0080] Among them, C W Let C be the propagation speed of a transverse wave in water, which is 1500 m / s; S The propagation speed of the transverse wave in the steel is 3230 m / s.

[0081] When the reflection angle β = 90°, there exists a critical angle.

[0082]

[0083] like Figure 6 As shown, based on the critical angle of shock wave incidence and the explosion distance of the scaled-down model contact explosion, it can be seen that the axial dimension of the scaled-down model must meet the constraint condition of the critical angle. After calculation, it can be seen that the axial distance of the designed submarine target model meets the constraint condition of the critical angle of shock wave incidence.

[0084] L<2R m ·tan27.7°

[0085] (3) Design of load-bearing steel cable length

[0086] Each submarine target is equipped with four lifting lugs, one above and one below. The blast distance ballast is connected to the lower lifting lug of the target via a load-bearing steel cable.

[0087] F 浮筒实际的排水量 +F 模型排水量 +F 压载排水量 =G 浮筒质量 +G 模型质量 +G 压载质量

[0088] Based on the ratio of actual drainage volume to total drainage volume, calculate the ratio of the area of ​​S2 to the area of ​​the circle, such as... Figure 7 , 8 As shown in Figure 9, calculate α and S1 according to the formula, and find the length of L according to the formula.

[0089] S1=r1 cos a sin a

[0090]

[0091] S1 is the area of ​​the triangle formed by the waterline and the dot on the circular surface, which is the area of ​​the impact-resistant pontoon before it is submerged, and the unit is m. 2 S2 represents the draft area of ​​the cylindrical surface, i.e., the draft area of ​​the impact-resistant pontoon, in meters (m²). 2 ; a is the included angle between the centers of the unsubmerged area, in degrees; r1 is the radius of the impact-resistant buoy;

[0092] L1=r1cosa

[0093] L1 is the distance between the waterline and the origin, that is, the distance between the center of the impact-resistant float and the water surface of the test pool, in meters.

[0094] d = r1 - L1

[0095] d represents the draft, in meters (m).

[0096] Next, based on the position of the model's lifting lug, the axial length G between the center point of the submarine target and the lifting lug can be calculated. Then, based on the test water depth h, the axial length G between the center point of the submarine target and the lifting lug, and the draft d, the length W can be calculated. Finally, the length J of the wire rope can be calculated.

[0097]

[0098] Where P is the lateral distance between the upper and lower lifting lugs; G is the axial length between the center point of the submarine target and the lifting lugs; P and G are determined by the dimensions of the pontoon and the model.

[0099] (4) Free field sensor deployment design

[0100] An adjustable free-field sensor deployment device allows for adjustment of the distance, depth, and number of free-field sensors by modifying its structural design. The following is the formula for calculating the underwater free-field shock wave pressure P(t):

[0101] Shock wave peak pressure P m (Unit: MPa) is shown below:

[0102]

[0103] Where l1 and k1 are experimental coefficients; α1 and β1 are impact pressure attenuation coefficients; R is the distance between the underwater free field sensor and the explosion center; and r2 is the explosion radius.

[0104] A test method for conducting a model device for underwater explosion damage to submarines at great depths within a limited water area includes:

[0105] (1) Select different types of submarine targets according to the test requirements. Through the watertight hatch on the target, the test personnel enter the target target to install sensors on the target structure. After the installation is completed, close the hatch and check the watertightness of the hatch.

[0106] (2) There are three types of sensors required for the test: one is the impact acceleration sensor, the second is the wall pressure sensor, and the third is the strain gauge. The impact acceleration sensor is connected to the metal base by threads, and then the metal base is welded to the measurement position inside the model. The wall pressure sensor is installed in the through hole of the model shell by threads, with the measuring head tangent to the model ring surface, and the installation position is kept watertight. The strain gauge is polished with a grinding wheel to produce a metallic luster, and then glued to the measurement position with strain gauge special glue. At this time, the sensor inside the model is installed. After the measurement data acquisition instrument channel makes good contact, the model chamber door is closed.

[0107] (3) Before the experiment, the four lifting lugs at the bottom of the impact-resistant float were connected to the four lifting lugs on the target through load-bearing steel cables, and the four lifting lugs at the bottom of the target were connected to the counterweight through steel cables.

[0108] (4) Once the test preparation is complete, the test will begin. The truck crane will first float the impact-resistant pontoon on the water surface, and then the truck crane will place the other components underwater in sequence. The distance between the submarine target and the pontoon will be adjusted according to the length of the load-bearing cable. At this time, the truck crane's work is completed and the model placement work is completed.

[0109] (5) Place the pre-installed free field sensor connecting rod on the water surface, adjust it to the correct position, and let the free field sensor with the connecting wire fall freely into the water to a certain depth to observe the stability of its measurement channel.

[0110] (5) The explosion source is connected to the connecting rod on the buoy by a thin line and is freely lowered to a certain depth. Since the explosion source should be positive buoyancy, a small ballast block, such as a weight, is attached to the lower end.

[0111] (6) Check the integrity and functionality of the test cable. If there are no problems, start the test.

[0112] (7) After the test, the truck crane pulled the heavy model out of the water and placed it on the bank of the explosion pool by pulling the impact-resistant pontoon.

[0113] This testing technique was used to complete a damage test of a submarine explosion model in a limited water area at great depth. The test model, weighing 3 tons, was hoisted to a depth of 15m in the explosion pool. Thirty structural response data points were measured inside the model, and four data points were measured outside the model at a depth of 15m, explosion distances of 3m, 5m, and 7m, and free field pressure. The test data showed good results. After the test, the model was pulled out of the water and its state was adjusted. The impact-resistant floats showed no deformation, and the next test could be carried out quickly.

[0114] In summary, this invention relates to a method (including measurement) for conducting underwater explosion damage model tests on submarines in confined waters at great depths. The aim is to study the impact damage of underwater explosion-generated shock waves on submarines, thereby addressing the problem of the damage characteristics of submarine hull structures under the impact of underwater explosions. This device simulates the structure and environment of the submarine and the explosion site, primarily for experimental research on the damage characteristics of underwater explosion-generated shock waves on the hull structure. The device is reusable, easy to control, convenient to disassemble, and reduces experimental costs.

[0115] The above description is merely a specific embodiment of the present invention. The technical features of the present invention are not limited thereto. Any other implementation methods derived by those skilled in the art without departing from the technical solution of the present invention should be covered within the patent scope of the present invention.

Claims

1. A device for modeling the damage of submarines in deep underwater explosions within a limited water area, characterized in that, Includes a water tank, testing equipment, free-field pressure sensor, and explosion source; The testing device is arranged inside a water tank, with a blast source fixed on one side by a blast source positioning rod. The testing device includes an impact-resistant buoy and a submarine target. The impact-resistant buoy suspends the submarine target inside the water tank via a load-bearing steel wire rope, and the impact-resistant buoy is located on the surface of the water tank. A ballast connected to the bottom of the submarine target via a load-bearing steel wire rope is arranged. Free-field pressure sensors connected to the impact-resistant buoy via an adjustable free sensor deployment device are arranged around the testing device.

2. The device for modeling the damage of a submarine in deep underwater explosion within a limited water area as described in claim 1, characterized in that, The impact-resistant buoy includes a single tube; multiple single tubes are connected by a transverse stabilizing plate; each single tube is a cylindrical cover plate with uniformly arranged annular ribs inside; the inner wall of the cylindrical cover plate is provided with T-shaped beam reinforcing ribs; the submarine target is provided with a watertight hatch.

3. The device for modeling the damage of a submarine in deep underwater explosion within a limited water area as described in claim 1, characterized in that, The distance between the submarine target and the explosion source is designed based on an equal impact factor: Among them, W p The amount of explosive charge used in the prototype test; R p For prototype test detonation distance; W p The amount of explosive charge for submarine target testing; R m The test range for submarine target blasting; Where D is the maximum diameter of the bubble; H is the water depth of the prototype test; H0 is the prototype atmospheric pressure head; J w These are empirical constants related to the properties of explosives.

4. The device for modeling the damage of a submarine in deep underwater explosion within a limited water area as described in claim 1, characterized in that, The radius of the submarine target section is designed based on the spherical wave effect: Where, r m r is the radius of the submarine target section. p The radius of the prototype module; The obtained submarine target section radius r m With the prototype section radius r p The ratio is used to determine the geometric scaling factor of the submarine target size.

5. The device for modeling the damage of a submarine in deep underwater explosion within a limited water area as described in claim 1, characterized in that, The axial length L of the submarine target needs to meet the critical angle constraint condition for shock wave incidence: Among them, C w C is the speed at which a transverse wave propagates in water. s Let be the propagation speed of the transverse wave in the steel.

6. The device for modeling the damage of a submarine in deep underwater explosion within a limited water area as described in claim 1, characterized in that, The explosion source depth l is based on the submarine target radius r. 靶标半径 and the axial length L of the impact-resistant pontoon 抗冲击浮筒 Design it:

7. The device for modeling the damage of a submarine in deep underwater explosion within a limited water area as described in claim 1, characterized in that, The load-bearing steel wire ropes are respectively connected to the lower lifting lug at the bottom of the impact-resistant buoy and the upper lifting lug at the top of the submarine target. The length J of the load-bearing steel wire rope is: Where P is the lateral distance between the upper and lower lugs; W is the distance between the submarine target and the impact-resistant buoy. Where h is the test water depth; d is the draft of the impact-resistant pontoon; G is the axial length between the center point of the submarine target and the lifting lug; β is the angle between the center point of the submarine target and the direction of the lifting lug; r1 is the radius of the impact-resistant pontoon; and L1 is the distance between the center of the impact-resistant pontoon and the surface of the test pool.

8. The device for modeling the damage of a submarine in deep underwater explosion within a limited water area according to claim 7, characterized in that, The actual displacement F of the impact-resistant pontoon 浮筒实际的排水量 According to the submarine's mass G 模型质量 Ballast mass G 压载质量 Impact-resistant pontoon mass G 浮筒质量 Submarine mass displacement F 模型排水量 Ballast Displacement F 压载排水量 Design it: F 浮筒实际的排水量 +F 模型排水量 +F 压载排水量 =G 浮筒质量 +G 模型质量 +G 压载质量 The draft area of ​​the impact-resistant pontoon is calculated based on the ratio of the actual discharge volume to the total discharge volume. Then, the undrafted area is calculated using the total area of ​​the impact-resistant pontoon, thereby calculating the distance between the center of the impact-resistant pontoon and the water surface of the test pool. L1=r1 cosa Where S1 is the area of ​​the impact-resistant pontoon that is not submerged; S2 is the area of ​​the impact-resistant pontoon that is submerged; and a is the angle between the centers of the areas that are not submerged.

9. The device for modeling the damage of a submarine in deep underwater explosion within a limited water area as described in claim 1, characterized in that, The distance R between the underwater free-field sensor and the explosion center, and the explosion radius r2, are determined based on the required peak pressure P in the experiment. m Design it to satisfy the following relationships: Where l1 and k1 are experimental coefficients; α1 and β1 are impact pressure attenuation coefficients.

10. A test method for conducting a deep-sea underwater explosion damage model device in a limited water area as described in claims 1-9, characterized in that, Includes the following steps: Step 1: Select submarine targets of different sizes according to the test requirements. Personnel enter the target through the watertight hatch to deploy sensors. After deployment, close the hatch and check its watertightness. The sensors include an impact acceleration sensor, a wall pressure sensor, and strain gauges. The impact acceleration sensor is threaded onto the metal base of the submarine target, and the metal base is then welded to the measurement position inside the model. The wall pressure sensor is threaded into a through-hole in the model's outer shell, with the measuring head tangent to the model's toroidal surface, and the installation position is kept watertight. The strain gauge attachment position is polished with a grinding wheel to a metallic luster, and then adhered to the measurement position using strain gauge adhesive. Step 2: Connect the lower lifting lug of the impact-resistant pontoon to the upper lifting lug of the submarine target using a load-bearing steel wire rope. Connect the lower lifting lug of the target to the ballast using a steel wire rope. Step 3: Adjust the length of the load-bearing steel wire rope between the impact-resistant pontoon and the submarine target according to the target parameters, float the impact-resistant pontoon on the water surface, and put the submarine target into the water; Step 4: Place the pre-installed free field sensor connecting rod on the water surface, adjust it to the correct position, and let the free field sensor with the connecting wire fall freely into the water to a certain depth to observe the stability of its measurement channel. Step 5: The blast source is connected to the connecting rod on the pontoon via a thin line and is lowered freely to a certain depth, with the lower end of the blast source bearing a ballast load; Step 6: Check the test cable. If there are no problems, start the test; test the explosion response at different distances.

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