| Thermobaric explosive(TBE)is a kind of typical nonideal explosive.Its process of energy output is different from other conventional explosives.In order to study its characteristics in confined space,this dissertation made a theoretical calculation and numerical simulation to study its explosion characteristics.Aiming at the application of TBE,on the basis of calculating the explosive parameters,a series experiments in confined space were designed.The effects of aluminum powder size and content,type of oxidants and component ratio on blast parameters were studied.The main research results are as follows:Through theoretical analysis and experience formulas,the law of the influence on the post combustion performance of the main components of thermobaric explosives was studied.The effect laws of the contents of aluminum and KP on the after-burning of thermobaric explosives were acquired by means of energy calculation software.Then the methods to improve the post combustion heat and the post combustion temperature were put forward in this paper.Through confined space tests,the influence of aluminum on explosive energy output of thermobaric explosive were studied.The DSC was used to study the thermal decomposition of the thermobaric explosives with different particle sizes of aluminum powder.The overpressure and impluse of TBE containing 30%aluminum are slightly higher than other formulas.The test results shows that aluminum particle size has a great influence on the explosion energy of thermobaric explosive in confined space,the overpressure of 2#sample with particle a mean size of 3 μm is at least 6.0%higher than 1#sample with an average particle size of 40 nm at each distance,and more than 10%higher than 3#sample with particle size of 35 μm at each distance,the thermal stability of three samples reduces with the decrease of aluminum particle size,the biggest falling range of activation energy is 31.1%,the maximum value of TPO is reduced by 11.7 ℃.Numerical simulation of 4#and 5#samples,the errors of overpressure,impulse and the quasi-static pressure of the shock wave between experiment and simulation are so small that it can be neglected,The error is controled within 9%.The energy release law in confined space was studied by designing different formulas of thermobaric explosive.There is little affect of oxidant species on shock wave.The overpressure and impulse of the formula containing AP is higher than the formula containing KP.The peak temperature of TBE containing AP is higher than that containing KP,and the decay rate is faster.Adding more HMX can increase the peak overpressure and impulse.Increaseing the content of KP can make positive phase time larger.When the ratio of HMX/(HMX+KP)is below 0.83,the maximum temperature of the fireball increased with the increment of the content of KP. |
