Rapid cook-off test device and method

Abstract

The invention relates to the technical field of ammunition cook-off tests, and particularly discloses a rapid cook-off test device and method.The device comprises a supporting frame, an oil pool, a lifting appliance, a thermocouple, a speed measuring target, a verification plate, a pressure sensor, a video recording device, a temperature recorder and the like. The oil pool is arranged below the supporting frame, the hanger hangs the test bomb above the oil pool, the thermocouple surrounds the test bomb, the speed measuring target and the verification plate are arranged in front of and behind the test bomb respectively, and the pressure sensor is arranged on the side face. The method comprises the steps of inspection before test, equipment installation, verification plate arrangement, sensor installation, equipment debugging, test bomb fixing, water injection and oil injection, remote ignition, observation and recording, field investigation, photographing and recording, unreacted test bomb destroying and the like. The rapid cook-off environment can be accurately simulated, the temperature change of the test bomb can be comprehensively monitored, key parameters can be comprehensively and accurately measured, reliable data can be provided for test bomb performance evaluation, and the test is safe and reliable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ammunition cook-off test, in particular to a rapid cook-off test device and method. BACKGROUND

[0002] The rapid cook-off test, also known as liquid fuel / external ignition test, is used to study the effects of ambient fires in storage and readiness conditions on conventional ammunition and its subsystems when the ammunition is in the flame center area or the marginal zone.

[0003] It is crucial to accurately obtain and analyze key parameters such as the reaction characteristics of the test ammunition, the dispersion of fragments, and the shock wave pressure under the rapid cook-off environment. However, existing test devices and methods have many shortcomings in simulating the rapid cook-off environment, accurately measuring various parameters, and ensuring test safety. For example, some devices cannot comprehensively and accurately monitor the temperature changes around the test ammunition, cannot accurately measure the fragment velocity and shock wave pressure, and may have safety hazards during the test process, which cannot effectively ensure the safety of the test personnel and equipment.

[0004] Therefore, a rapid cook-off test device and method have become a problem that people urgently need to solve. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a rapid cook-off test device and test method that can accurately simulate the rapid cook-off environment, comprehensively and accurately measure various key parameters of the test ammunition during the cook-off process, such as temperature, fragment velocity, shock wave pressure, etc., while ensuring the safety and reliability of the test process, and providing strong data support for the performance evaluation and research of the test ammunition.

[0006] To solve the above technical problems, the technical solution provided by the present application is as follows: a rapid cook-off test device, comprising a support frame, an oil pool, a lifting appliance, a thermocouple, a velocity measuring target, a verification plate, a pressure sensor, a video recording device, and a temperature recorder;

[0007] The oil pool is arranged below the support frame, the lifting appliance is suspended on the support frame and above the center of the oil pool, the lower end of the lifting appliance is fixed with the test ammunition, the thermocouple is arranged around the test ammunition, the velocity measuring target is arranged behind the test ammunition, the verification plate is arranged in front of the test ammunition, the pressure sensor is arranged in the vertical direction of the straight line passing through the velocity measuring target and the verification plate, the video recording device is arranged to face the test ammunition, and the temperature recorder displays the temperature monitoring data of the thermocouple.

[0008] Further, the thermocouple is arranged at least six and located at the upper, lower, left, right, front, and rear of the test ammunition.

[0009] Further, the thickness of the verification plate is selected by the following method:

[0010] According to the fragment penetration formula Theoretically calculate the maximum target plate thickness that can be penetrated at the distance X from the explosion center, which is the maximum penetration depth p of the corresponding material, and the verification plate thickness is not greater than p / 2.

[0011] Wherein, p is the penetration depth, unit m; m is the mass of the fragment, unit g; v is the actual speed of the fragment at the distance X from the explosion center or the calculated theoretical fragment speed V x , unit m / s; k1, k2 are constants, for steel or iron verification plate k1=0.21cm 3 / KJ.

[0012] Further, the determination method of the theoretical fragment speed is as follows:

[0013] Theoretical fragment speed: V x =V0e -ax ;

[0014] Wherein, ρ0 is the air density; C D is the drag coefficient; m is the mass of the fragment; A is the windward area of the fragment;

[0015] The fragment includes natural fragment and prefabricated fragment;

[0016] For natural fragments: the drag coefficient C D is 1.21;

[0017] The prefabricated fragment includes spherical prefabricated fragment, equal cubic fragment and equilateral polygon fragment;

[0018] For prefabricated fragments: the drag coefficient C D of the spherical prefabricated fragment is 0.93, the drag coefficient C D of the equal cubic fragment is 1.14, and the drag coefficient C D of the equilateral polygon fragment is 1.1;

[0019] For the windward area of the spherical fragment with known radius: A=πr 2 ;

[0020] For the windward area of the spherical fragment with known mass:

[0021] m is the mass of the fragment, unit g; ρ is the metal density of the fragment, or the density of Fe 7.784g / cm 3 is replaced.

[0022] Further, the material of the verification plate adopts Q235 carbon structural steel stipulated by GB / T700-2006.

[0023] Further, the video recording device comprises a video camera and a camera.

[0024] Further, the oil pool adopts a cuboid steel furnace bed, the length of the oil pool is 1.6-2.0 m, the width is not less than 30 cm, and the depth is not less than 0.3 m; the oil pool stores fuel oil, and the bottom of the oil pool also stores liquid water, the fuel oil floats above the liquid water, and the depth of the liquid water is not less than 0.1 m.

[0025] Further, the initial height of the test bomb and the fuel oil liquid surface is determined according to the flame height, and is required to be not less than 0.3 m, so as to ensure that the test bomb is completely in the flame during the test process.

[0026] Further, the determination method of the flame height is as follows:

[0027] Flame height:

[0028] Wherein, h is the flame height, the unit is m; r is the radius of the liquid pool, the unit is m; ρ0 is the air density; v is the burning speed, the unit is kg / (m 2 ·s); g is the acceleration of gravity, 9.8 m / s 2 ;

[0029] Wherein, the radius r of the liquid pool is equivalent to the burning surface area of the fuel oil: The cross-sectional area S of the oil pool is L*W, wherein L is the length of the fuel oil liquid surface, and W is the width of the fuel oil liquid surface.

[0030] The application also provides a rapid roasting and burning test method, comprising the following steps:

[0031] S1, checking the test bomb before the test and taking photos, calibrating all test and measurement equipment to ensure that the equipment is working properly;

[0032] S2, installing the oil pool and the supporting frame;

[0033] S3, arranging the verification plate and the wind shield according to the distance between the test bomb and the verification plate recorded in experience or historical records;

[0034] S4, installing the shock wave pressure sensor, and arranging the fragment velocity measurement equipment for the blast test bomb;

[0035] S5, installing and debugging the video recording device and the monitoring system, and taking corresponding protective measures for the signal line;

[0036] S6, debugging the test equipment to ensure that the state is good;

[0037] S7, the test bomb is fixed on the support frame by the lifting appliance, located in the middle of the horizontal axis of the oil pool area, and the thermocouples are arranged and fixed on the test bomb in up, down, left, right, front and back directions;

[0038] S8, water is injected into the oil pool to not less than 10cm; fuel oil is injected into the oil pool, and the amount of fuel oil meets the requirement that the burning time is not less than 15min; and the test bomb is adjusted to the height of the liquid level of the oil pool;

[0039] S9, the remote ignition device is laid out; multiple points are required to be ignited at the same time, and the ignition distance meets the safety distance requirement;

[0040] S10, the on-site personnel are evacuated to the safety area, the recording equipment and the temperature measuring recording equipment are started, and the remote ignition device is ignited;

[0041] S11, the flame burning temperature, the test bomb reaction time and the video image of the reaction process are observed and recorded;

[0042] S12, after confirming safety, on-site investigation is carried out; whether there is debris nearby is checked, and the debris characteristics including position, size, shape, integrity and scattering distance are recorded; the rapid cooking device and the test bomb debris are photographed; the damage of the test device, the verification plate perforation, indentation and deformation, and the ground craters are photographed;

[0043] S13, the unreacted test bomb and the charge are destroyed.

[0044] Compared with the prior art, the present application has the following advantages:

[0045] The test device of the present application can accurately simulate the rapid cooking environment by reasonably designing the oil pool structure and the fuel oil liquid level, and combining the flame height determination method, so as to provide stable and actual cooking conditions for the test bomb.

[0046] The present application adopts multiple thermocouples arranged in all directions, which can accurately monitor the temperature change around the test bomb; by reasonably setting the speed target and the pressure sensor, and combining the scientific calculation method of the fragment velocity and the shock wave pressure, the key parameters of the test bomb in the cooking process can be comprehensively and accurately measured, so as to provide detailed and reliable data for the performance evaluation and research of the test bomb.

[0047] In the test device design and test method, the safety factors are fully considered, such as setting the remote ignition device, reasonably determining the ignition distance, evacuating the test personnel to the safety area, etc., so as to effectively guarantee the safety and reliability of the test process, and avoid personnel injury and equipment damage. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 is a structural schematic view of a rapid cooking test device of the present application.

[0049] Figure 2 Figure 1 is a layout diagram of a rapid cook-off test device according to the present application.

[0050] As shown in the figure: 1, support frame, 2, oil pool, 3, sling, 4, thermocouple, 5, speed target, 6, verification plate, 7, pressure sensor, 8, video device, 9, temperature recorder, 10, fuel oil, 11, liquid water, 12, test projectile. DETAILED DESCRIPTION

[0051] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "inner", "outer", "vertical", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0052] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0053] The present application will be further described in detail below in combination with the drawings.

[0054] In combination with the drawings Figures 1-2 , the specific implementation process of the rapid cook-off test device and method according to the present application is as follows:

[0055] Example 1: Test device

[0056] A rapid cook-off test device, comprising a support frame 1, an oil pool 2, a sling 3, a thermocouple 4, a speed target 5, a verification plate 6, a pressure sensor 7, a video device 8 and a temperature recorder 9.

[0057] The oil pool 2 is arranged below the support frame 1, and adopts a cuboid steel furnace bed with a length of 1.6-2.0 m, a width of not less than 30 cm and a depth of not less than 0.3 m. The oil pool 2 stores fuel oil 10, and also stores liquid water 11 at the bottom. The fuel oil 10 floats above the liquid water 11, and the depth of the liquid water 11 is not less than 0.1 m.

[0058] The lifting appliance 3 is hung on the support frame 1 and is in the center above the oil pool 2, the lower end of the lifting appliance 3 is fixed with the test bomb 12, the initial height of the test bomb 12 and the fuel 10 liquid surface is determined according to the flame height, and is required to be not less than 0.3 m, so as to ensure that the test bomb 12 is completely in the flame during the test process.

[0059] The thermocouple 4 is provided with a plurality of thermocouples, at least six thermocouples are provided and are located at the upper, lower, left, right, front and rear of the test bomb 12, so as to comprehensively monitor the temperature change around the test bomb 12, and the temperature recorder 9 displays the temperature monitoring data of the thermocouple 4.

[0060] The speed measuring target 5 is arranged behind the test bomb 12, and the verification plate 6 is arranged in front of the test bomb 12. The material of the verification plate 6 is Q235 carbon structural steel specified in GB / T700-2006, and the thickness is selected according to the fragment penetration formula.

[0061] The pressure sensor 7 is provided with at least three pressure sensors and is arranged in the vertical direction of the straight line where the speed measuring target 5 and the verification plate 6 are located, so as to accurately measure the shock wave pressure.

[0062] The shooting direction of the video recording device 8 is towards the test bomb 12, and the video recording device 8 includes a camera and a camera, and is used for recording video images during the test process.

[0063] Embodiment 2: Test method

[0064] I. Determination of combustion environment

[0065] 1. Fuel selection

[0066] The rapid cook-off test method of the application can select suitable liquid hydrocarbon fuels including JP-4, JP-5, Jet A-1, commercial kerosene and the like.

[0067] The test bomb belongs to shipborne ammunition, and considering the influence of the shipborne aircraft, there is a possibility that fuel leakage and residue appear on the deck, aviation kerosene is selected as the fuel for rapid cook-off;

[0068] Considering that the fuel used by the ammunition and the weapon platform carrying vehicle is diesel (diesel is generally used as power fuel for ground weapon equipment of the army in China), diesel and 3# aviation kerosene are selected as fuels for rapid cook-off test comparison.

[0069] The fuel material meets the requirement that the combustion time of each time is not less than 15 min. The combustion rate v of the fuel is calculated according to the "pool fire model-semi-empirical model (used for describing the geometric and radiation characteristics of pool fire)", that is, the burning speed of unit area is combined with the size of the oil pool to calculate the total amount of fuel required, the flame height and the like. The combustion rate v of the fuel is calculated according to the formula , the total amount of fuel required for 15 min is calculated according to the formula ; wherein, S is the burning rate of unit surface area, unit is kg / (m 2 ·s); H c is the liquid combustion heat, unit is: J / (kg·k); C p is the specific constant pressure heat capacity of the liquid, unit is: J / (kg·k); T b is the boiling point of the liquid, unit is: K; T0 is the ambient temperature, unit is: K; H is the vaporization heat of the liquid, unit is J / kg; S is the inner surface area of the oil pool, unit is: m 2 .

[0070] The burning rate of diesel oil is 14g·m 2 / s, and the burning rate of aviation kerosene is 15g·m 2 / s.

[0071] 2, burning condition

[0072] The test bomb (with dummy fuze) is heated by exposing it to the burning aviation kerosene flame until the test bomb reacts or reaches the specified time.

[0073] (1) Oil pool (furnace bed) design

[0074] The size of the oil pool is designed according to the requirement that the fuel tank is large enough and at least 1m away from the first side of the test sample. Considering that the shape of the ammunition is generally similar to a long cylinder, the oil pool is designed as a rectangular steel furnace bed for storing fuel. At the same time, considering that the length-width ratio of the "pool oil model" cannot be too large, the accuracy of the flame height estimation is improved while ensuring the flame temperature.

[0075] Oil pool size design: take a high-power live ammunition as an example. Length, the front and back sides of the test bomb are not less than 30cm, the design length is 1.6-2.0m, and the actual processing length is 1.8m; width, the left and right sides of the test bomb are not less than 30cm, the design width is greater than 1.0m, and the actual processing width is 1.4m.

[0076] (2) Fuel and fuel quantity

[0077] According to the calculation formula of the total amount of fuel, the total amount of aviation kerosene and diesel oil required for single fast baking test is 43.6L and 37.4L respectively. The fuel depth in the oil pool is calculated to be 0.174m and 0.015m respectively, the water storage depth at the bottom of the oil pool is not less than 0.1m, the design depth of the oil pool is not less than 0.3m, and the actual processing depth is 0.35m.

[0078] (3) Position and installation of test bomb

[0079] The test bomb is located in the middle of the oil pool above the initial height of the fuel surface, which is determined according to the flame height, generally not less than 0.3m, to ensure that the tested product is completely in the flame during the test process.

[0080] Flame height:

[0081] Wherein, h is the flame height, unit is m; r is the radius of the liquid pool, unit is m; p0 is the air density; v is the burning speed, unit is kg / (m 2 ·s); g is the acceleration of gravity, 9.8m / s 2 ;

[0082] Wherein, the radius r of the liquid pool is equivalent to the surface area of the fuel burning: The cross-sectional area S of the oil pool is LxW, wherein L is the length of the fuel surface, and W is the width of the fuel surface.

[0083] After entering the data for calculation, the radius r of the liquid pool is 0.798m, and the flame height of diesel and aviation kerosene during combustion can be estimated as follows: h 柴油 =0.8m; h 航空煤油 =0.9m.

[0084] Support frame during suspension and placement: steel support frame, test bomb fixed by clamp, clamp fixed on support frame by chain suspension through lifting device, length adjustable between 0.2-0.6m.

[0085] 3. Test site

[0086] The test site is required to be flat and far away from residential areas, to meet the requirements of test bomb expected reaction level and fragment scattering distance, to determine the safety distance and warning requirements according to the test bomb detonation requirements. To prevent long-distance throwing of debris and facilitate recovery.

[0087] When there is wind, windbreaks (color steel plates or plywood, etc.) are arranged in the direction of the wind, which is required not to affect the shock wave test and video recording field of view. When the wind speed is large (wind speed>8m / s), the test is stopped.

[0088] Considering that the combat environment is generally natural environment, the liquid fuel combustion conditions are affected by climate conditions, and when the environmental temperature is relatively low (<15℃), the ignition speed and flame temperature rising speed are relatively low, which can not be required, only the duration of the test ammunition reaction before the flame temperature rises to the specified temperature and stably burns is tested.

[0089] II. Test content

[0090] Test items include: test bomb environment (fire field) temperature, shock wave pressure, verification plate deformation (bending, perforation, indentation and throwing), post-test site conditions (ground ablation, blast crater, combustion pool damage, etc.), and test process video.

[0091] 1. Data recording

[0092] a. Time for flame temperature to rise to 550°C;

[0093] b. Average temperature from when temperature reached 550°C to when the test article began to react;

[0094] c. Temperature change over time;

[0095] d. Time when reaction began;

[0096] e. Post-reaction shock wave overpressure value;

[0097] f. Shell fragmentation condition, internal ablation condition (if explosion did not occur);

[0098] g. Post-test site condition (ground ablation, crater, burn pit damage, charge ejection, etc.);

[0099] h. Verification plate deformation (bending, perforation, indentation, and ejection).

[0100] 2. Photography and video recording

[0101] a. Static photos of test projectile before and after test;

[0102] b. Verification plate deformation (bending, perforation, indentation, and ejection) photos;

[0103] c. Recovered fragments, ejected charge;

[0104] d. Post-test site photos;

[0105] e. Test process video recording.

[0106] The entire test process is recorded using a common video camera. In order to prevent the flame from being affected by external wind during the test process, a wind barrier is set up at an appropriate distance, and the wind barrier is higher than the flame height.

[0107] III. Selection of measuring instruments and equipment

[0108] a. Temperature measurement

[0109] Thermocouple: WERNK-191 armored thermocouple is used

[0110] Thermocouple temperature resistance ≥ 1200°C; temperature measurement accuracy ± 5°C; quantity ≥ 6, one each on the top, bottom, left, right, front, and back of the test article, with 2 spares.

[0111] b. Time recording equipment: ECR7100 intelligent recorder is selected, with a sampling rate not less than 1 time / second.

[0112] c. Shock wave pressure sensor

[0113] The pressure sensor can be selected as ground reflection type or free field sensor, but the consistency of test conditions must be ensured. The number and position of pressure sensors meet the requirements of GJB 6390.3-2008 6.1, and the number is not less than 3, and the directionality of the shock wave is fully considered. A single test projectile without obstruction around is generally considered to be uniformly distributed.

[0114] The numerical value of the shock wave overpressure is set according to the peak value causing damage to personnel (see Table 3-14). The layout distance is generally determined according to the distance corresponding to the theoretical value of 0.1 MPa of the shock wave overpressure of the charge.

[0115] Table 1: Damage degree of shock wave overpressure to exposed personnel

[0116] Degree of injury Injury description Shock wave overpressure threshold (MPa) Mild Mild bruising 0.02～0.03 Moderate Injury to auditory organs, moderate bruising, fractures, etc. 0.03～0.05 Severe Severe internal bruising, can cause death 0.05～0.1 Extremely severe Most people die ≥0.1

[0117] The formula can be used to calculate the shock wave overpressure generated after the test projectile charge detonation; wherein, ΔP mG is the shock wave overpressure, unit: MPa; R is the distance from the explosion center, unit: m; w is the TNT equivalent of the main charge, unit: kg.

[0118] Taking a certain live ammunition as an example, w = 13.95, shock wave pressure sensors are laid at different distances between 8-20m, and the measured shock wave overpressure value is compared with the shock wave intensity value at the same distance of the static explosion power to determine the reaction level.

[0119] Table 2: Corresponding relationship between theoretical value of shock wave overpressure of 155mm large power projectile and distance, equivalent

[0120] Shock wave overpressure (MPa) TNT equivalent (kg) Distance (m) 0.02 13.95 20 0.1 13.95 8.05

[0121] d. Verification plate

[0122] The verification plate is used to verify whether the explosion fragments are generated and the penetration strength of the formed fragments. Steel material which is easy to obtain in the market and relatively low in cost is selected as the target plate material of the verification plate. In order to ensure the consistency of test results and the comparability of different warhead data, Q235 carbon structural steel specified in GB / T700-2006 is used as a unified standard.

[0123] The layout distance of the verification plate and the thickness of the target plate of the verification plate. For preformed fragments, the fragment velocity and penetration theory can be used for estimation. For natural fragments, appropriate target plates and layout distances are generally selected according to previous experience or data.

[0124] The theoretical fragment velocity corresponding to the distance is calculated according to the natural fragments and the preformed fragments respectively: V x = V0e -ax ; wherein, p0 is air density; C D is drag coefficient; m is mass of fragment; A is windward area of fragment;

[0125] The fragment includes natural fragment and preformed fragment.

[0126] For natural fragment: drag coefficient C D Usually 1.21; the windward area of fragment is the average projection area of 16 faces of a group of typical fragments measured actually.

[0127] For natural fragment, the static explosion power test historical data of the warhead (fragmentation bomb, natural fragment) is used directly, the average fragment mass is 3.04 g, the initial speed of fragment is 1723.61 m / s, and the average speed of fragment at 6 m is 1338 m / s.

[0128] The preformed fragment includes spherical preformed fragment, equal cubic fragment and equilateral polygonal fragment; for preformed fragment: the drag coefficient C D of spherical preformed fragment is 0.93, the drag coefficient C D of equal cubic fragment is 1.14, and the drag coefficient C D of equilateral polygonal fragment is 1.1.

[0129] For the windward area of spherical fragment with known radius: A = πr 2 .

[0130] For the windward area of spherical fragment with known mass: Wherein, m is the mass of fragment, unit g; p is the density of fragment metal, or the density of Fe 7.784 g / cm 3 is used instead.

[0131] The selection and layout of verification plate, the spherical preformed fragment is according to the fragment penetration formula p = k2m 1 / 3 v 2 / 3 , Theoretical calculation is carried out, the maximum target plate thickness that can be penetrated at the distance X from the explosion center is the maximum penetration depth p of corresponding material, the thickness of verification plate is not greater than p / 2; wherein, p is penetration depth, unit m; m is fragment mass, unit g; v is the actual speed of fragment at the distance X from the explosion center or the theoretical fragment speed V x calculated, unit m / s; k1, k2 are constants, for steel or iron verification plate k1 = 0.21 cm 3 / KJ, for other material target plate, k1 can be equivalent conversion.

[0132] The verification plate of the test is selected and laid out according to the maximum penetration depth of 10 mm of the spherical prefabricated fragment to the steel plate at 6 m, 4 mm and 10 mm Q235 steel plates are selected as the verification plate, the size is 1.2 m*2 m, the number is 2-4 blocks, the initial layout distance is 6 m, and the distance is appropriately adjusted to 8 or 10 m according to the fragment penetration condition; the test data such as fragment indentation and perforation are recorded.

[0133] e.Camera and camera

[0134] The test should ensure the best field of view of the test object and the surrounding, and the test process is recorded completely, the action time is recorded by the Oda AC7 camera: 1280*760 / 120fps, 640*480 / 240fps, and the video recording working time is not less than 30 min. The whole test process is recorded by the Z82 camera or other video monitoring equipment with video storage function.

[0135] Explosion process: V711 type high-speed video, frame frequency 7530 frames / s, time resolution 1280*800 pixels.

[0136] f.Control mode

[0137] 1.Ignition: electric ignition mode, remote ignition of fuel oil.

[0138] 2.Flame temperature: after the temperature of any two thermocouples reaches 550 DEG C after the ignition of fuel oil, the timing starts, and the average temperature from the time when the flame temperature reaches 550 DEG C to the start of the reaction should be not less than 800 DEG C.

[0139] 3.Test time: fast baking time >= 15 min or the test bomb occurs violent reaction.

[0140] Four, test process

[0141] The fast baking test steps are as follows:

[0142] 1.Before the test, check the test bomb and take pictures, calibrate all test and measurement equipment to ensure that the equipment is working properly;

[0143] 2.Install the oil pool (furnace bed) and support frame;

[0144] 3.Arrange the verification plate and wind shield at a certain distance from the warhead according to the description of the verification plate in the selection of measurement instruments and equipment;

[0145] 4.Install the shock wave pressure sensor according to the requirement of the pressure sensor in the selection of measurement instruments and equipment, and the fragment velocity measurement equipment can be selected to be arranged for the blast test bomb;

[0146] 5.Install and debug the video recording device and monitoring system, and take appropriate protective measures for the signal line;

[0147] 6. Debugging test equipment to ensure its state is good;

[0148] 7. Fix the test bomb on the support frame in the middle of the horizontal axis of the oil pool area, and fix the thermocouples on the upper, lower, left, right, front and back of the warhead;

[0149] 8. Fill water in the oil pool to a certain height, generally not less than 10 cm; inject fuel into the oil pool, the amount of fuel meeting the specified requirements, and adjust the height of the warhead to the liquid level of the oil pool;

[0150] 9. Lay out the remote ignition device. Multiple points are required to be ignited at the same time, and the ignition distance meets the safety distance requirement;

[0151] 10. The on-site personnel retreat to the safety area, start the recording equipment and temperature measurement recording equipment, and ignite through the remote ignition device;

[0152] 11. Observe and record the flame combustion temperature, test bomb reaction time and other data (video images of the reaction process, etc.);

[0153] 12. After confirming safety, conduct on-site investigation. Check if there are any debris nearby, record the characteristics of the debris (position, size, shape, completeness, scattering distance, etc.), and take photos of the rapid cooking device and test bomb debris. Take photos of the damage of the test device, verification plate perforation, indentation, deformation, and ground craters, etc.;

[0154] 13. Destroy the unreacted test bomb and its charge.

[0155] Five, rapid cooking results evaluation

[0156] Through the reaction of the test bomb shell and charge after the test, the shock wave overpressure, the formation of fragments, the deformation and damage of the verification plate, the damage of the test device, the scattering of the charge, the ablation of the site, the explosion crater, etc., and the reaction of the test bomb observed in the test process video shooting, the rapid cooking reaction grade of the test bomb is comprehensively judged. The test of the fuse and primer does not evaluate the shock wave pressure, fragments, etc. due to the small amount of charge, and the reaction grade is determined by the test bomb firing observed by video and the shell ablation and damage after the test. The reaction grade of the rapid cooking of the test bomb and the judgment criteria are shown in Table 3.

[0157] Table 3: Reaction grade judgment criteria for rapid cooking of warhead

[0158]

[0159]

[0160] The above describes the present application and its embodiments, which are not limited, and the drawings only show one of the embodiments of the present application, and the actual structure is not limited thereto. In general, if a person skilled in the art is inspired thereby, without departing from the purpose of the present application, without creative design, similar structure and embodiments of the technical solution are not creative, and should belong to the protection scope of the present application.

Claims

1. A rapid cook-off test apparatus characterized by: The support frame, oil pool, sling, thermocouple, speed measuring target, verification plate, pressure sensor, video recording device and temperature recorder are included. The oil pool is arranged below the support frame, the sling is hung on the support frame and is above the center of the oil pool, the lower end of the sling is fixed with the test bomb, the thermocouples are arranged around the test bomb, the speed measuring target is arranged behind the test bomb, the verification plate is arranged in front of the test bomb, the pressure sensors are arranged in the vertical direction of the straight line on which the speed measuring target and the verification plate are arranged, the shooting direction of the video recording device is towards the test bomb, and the temperature recorder displays the temperature monitoring data of the thermocouples.

2. A rapid flash test apparatus according to claim 1, wherein: The thermocouples are arranged at least six and are respectively located at the upper, lower, left, right, front and rear of the test bomb.

3. A rapid flash test apparatus according to claim 2, wherein: The thickness of the verification plate is selected by the following method: According to the formula of fragment penetration p = k2m 1 / 3 v 2 / 3 、 Theoretical calculation is carried out, the maximum target plate thickness that can penetrate at the distance X from the explosion center is the maximum penetration depth p of the corresponding material, and it is verified that the plate thickness is not greater than p / 2. where p is the penetration depth, in meters; m is the mass of the fragment, in grams; v is the actual velocity of the fragment at a distance X from the blast center or the calculated theoretical fragment velocity V x , in meters per second; and k1, k2 are constants, with k1 = 0.21 cm 3 / KJ for steel or iron validation plates.

4. A rapid cook-off test apparatus as defined in claim 3, wherein: The determination method of the theoretical fragment velocity is as follows: Theoretical fragment velocity: V x = Voe -ax ; wherein, p0is the density of air; C D is the drag coefficient; m is the mass of the fragment; A is the windward area of the fragment; The fragments include natural fragments and prefabricated fragments. For natural fragments: drag coefficient C D Take 1.21; The prefabricated fragments include spherical prefabricated fragments, cubic fragments and equilateral polygonal fragments. For a spheroid: the drag coefficient C of the spheroid D Take 0.93, the drag coefficient C of the equicube D Take 1.14, the drag coefficient C of the equilateral D Take 1.1; For the wind area of a spherical fragment of known radius: A = πr 2 ; For a spherical fragment of known fragment mass, the windward area is: m is the mass of the fragment in g; p is the density of the fragment metal, or 7.784 g / cm3 for Fe 3 substitutions.

5. A rapid cook-off test apparatus as defined in claim 4, wherein: The material of the verification plate is Q235 carbon structural steel specified in GB / T700-2006.

6. A rapid cook-off test apparatus as defined in claim 5, wherein: The video recording device includes a camera and a photographic camera.

7. A rapid cook-off test apparatus as defined in claim 6, wherein: The oil pool is a cuboid steel furnace bed, the length of the oil pool is 1.6-2.0 m, the width is not less than 30 cm, and the depth is not less than 0.3 m, fuel oil is stored in the oil pool, liquid water is also stored at the bottom of the oil pool, the fuel oil floats above the liquid water, and the depth of the liquid water is not less than 0.1 m.

8. A rapid cook-off test apparatus as defined in claim 7, wherein: The initial height of the test bomb and the fuel oil liquid surface is determined according to the flame height, which is required to be not less than 0.3 m, so as to ensure that the test bomb is completely in the flame during the test process.

9. A rapid cook-off test apparatus as defined in claim 8, wherein: The determination method of the flame height is as follows: Flame height: where h is the flame height in meters, r is the radius of the pool in meters, p0is the air density, v is the burning velocity in kg / (m2s), and g is the acceleration due to gravity, taken to be 9.8 m / s2. 2 • s); g is the acceleration due to gravity, taken to be 9.8 m / s 2 ; Wherein, the pool radius r is equivalent to the fuel combustion surface area: The oil pool cross-sectional area S = L x W, wherein L is the fuel surface length, and W is the fuel surface width.

10. A rapid cook-off test method characterized by, The method comprises the following steps: S1, checking the test bomb before the test and taking a photo, calibrating all test and measurement equipment to ensure that the equipment is working properly; S2, installing the oil pool and the support frame; S3, arranging the verification plate and the wind shield according to the distance between the test bomb and the verification plate recorded in experience or historical records; S4, installing the shock wave pressure sensor, and arranging the fragment velocity measurement equipment for the blast test bomb; S5, installing and debugging the video recording device and the monitoring system, and taking corresponding protective measures for the signal line; S6, debugging the test equipment to ensure that it is in good condition; S7, fixing the test bomb on the support frame through the sling, which is located in the middle of the horizontal axis in the oil pool area, and arranging and fixing the thermocouples on the test bomb, below the test bomb, to the left of the test bomb, to the right of the test bomb, in front of the test bomb and behind the test bomb; S8, filling water in the oil pool to not less than 10 cm, and injecting fuel oil into the oil pool, the amount of fuel oil meeting the requirement of burning time of not less than 15 min, and adjusting the height of the test bomb to the liquid surface of the oil pool; S9, arranging the remote ignition device, which requires multiple points to be ignited at the same time, and the ignition distance meeting the safety distance requirement; S10, evacuating the on-site personnel to the safety area, starting the camera recording equipment and the temperature recording equipment, and igniting through the remote ignition device; S11, observing and recording the flame burning temperature, the test bomb reaction time and the video image of the reaction process. S12, after confirming safety, on-site investigation is carried out; it is checked whether there is wreckage nearby; wreckage characteristics are recorded, including position, size, shape, and completeness, scattering distance; and the rapid cook-off device and test bomb wreckage are photographed; the test device damage, verification plate perforation, indentation, deformation, and ground craters are photographed; S13, the unreacted test bomb and its charge are destroyed.

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