Research On Thermal Damage Effect Of Thermobaric Bomb Explosive

The explosion of thermobaric projectile has a very strong damage effect,which was first used in the battlefield.Subsequently,various countries carried out research and development one after another,and achieved certain research results.The explosion moment of thermobaric bomb will form a high-temperature and high-pressure field,accompanied by super shock wave,with great destructive force.This paper mainly studies the thermal damage effect of thermobaric bomb explosion,that is,the temperature information of fireball.In order to achieve the experimental purpose,the combination of fixed-point temperature measurement with tungsten rhenium thermocouple and infrared radiation temperature measurement is used to test the explosion field of thermobaric bomb.The principle of thermocouple temperature measurement and infrared temperature measurement are introduced respectively,and two different temperature measurement systems are built.According to the particularity of the measurement object,tungsten rhenium thermocouple with high temperature resistance and low price and cooled infrared thermal imager with wide temperature measurement range,high frame rate and high resolution are selected as the test equipment of this experiment.In view of different temperature measurement principles,the test accuracy of different temperature measurement systems is analyzed.The error of tungsten rhenium thermocouple temperature measurement system is mainly related to the material of thermocouple itself,manufacturing process and the accuracy of data acquisition system.Through the analysis one by one,the method of estimating the error is finally obtained.The error of infrared temperature measurement system is mainly related to the emissivity of the target and the attenuation of radiation in atmospheric transmission.It is difficult to determine the emissivity of fireball after the explosion of thermobaric projectile.In this experiment,the emissivity is set by determining the explosion product,and the value is 0.45.The factors causing the attenuation of infrared radiation in the atmosphere are analyzed in detail.Finally,the atmospheric transmittance is 73%.In the geometric calibration experiment,the proportional relationship between the actual spatial distance and the pixels of the infrared image is obtained;In the field calibration experiment,the attenuation law of the target temperature with the increase of the test distance is obtained.In the field explosion experiment of thermobaric bomb,the fixed-point temperature measurement experiment of "concentric circle" arrangement is carried out with tungsten rhenium thermocouple,and the variation law of temperature field in which the peripheral temperature of fireball is far lower than the internal temperature is obtained;The infrared thermal imager measures the explosion temperature field from different directions,and obtains the high temperature information,diameter,temperature field distribution and evolution process of the fireball.Finally,it is concluded that the maximum surface temperatures of the 2kg and6 kg explosive fireballs are 2197°C and 2881°C,respectively;the duration of the temperature field of their explosive fireballs with surface temperatures greater than 800°C is both 250 ms.The duration of 2kg in the temperature field above 1000°C is 220 ms,and the duration of 6kg in the temperature field above 1000°C is 200ms;the maximum diameter of the 2kg explosion fireball with surface temperature above 800°C and 1000°C is about 7.5m and 10.0m,6.2m and8.9m for the 6kg explosion fireball.The test results show that the temperature of fireball produced by thermobaric bomb explosion is very high,and the thermal damage effect is very strong within the diffusion range of its temperature field,which can destroy everything efficiently.The test system has strong reliability and simple operation,and can be widely used in the field of high temperature test.