Two-phase Flow Simulation Of After-burning Effect Of Thermobatic Explosive

Thermobaric explosive(abbreviated TBX)is an explosive that conventional explosives mixed with solid powder.When the explosive was detonated,the detonation products of conventional explosives and solid powder had an after-burning reaction,the process can significantly improve the energy release level of explosives and strengthen the shock wave effect and thermal effect.The thermobaric explosive is of great application value when we attack the personnel and equipment of the interior of the Confined space target(bunker,tunnel,ship compartment,etc.).Because the after-burning reaction of thermobaric explosive is a typical gas-solid two-phase flow process with chemical reaction,the mechanism is complex,and there is no reliable numerical simulation model and program to analyze it recently.In this paper,according to a kind of aluminum-containing thermobaric explosive,the after-burning reaction mechanism of detonation products gas and aluminum powder particle mixture Two-phase flow is studied,the corresponding numerical simulation model is established,and the finite difference calculation program is developed,and the explosion and the after-burning effect of the thermobaric explosive are numerically simulated and analyzed.The influence rule of the technological parameters of some aluminum powder particles on the explosive effect of thermobaric explosives was obtained.The main work of this paper is as follows:1,the basic theory of two-phase flow dynamics is reviewed,and a numerical simulation model of spherical symmetric one-dimensional gas-solid two-phase flow is established under the condition of explosive in air without boundary,and the model includes gas,particle motion control equations and corresponding gas-solid momentum,energy and mass transfer algorithm;2 A finite difference method for gas-solid two-phase flow explosion analysis is established,and two independent Lagrange grids are used to calculate the motion of the gaseous phase of detonation product and the particle phase of aluminum powder respectively,and the mechanical interaction of gas-particle,the reaction rate of the particle and the mass transfer of the gas-particle are taken into account to form the calculation program code TBX-1D;3 Under the condition of uniformly releasing energy in space,the calculation results of TBX-1D are tested by AUTODYN software,and then the explosion and the afterburning effect of thermobaric explosives are simulated and analyzed under various working conditions(with or without aluminum powder particles,reaction or not,different mass proportion and different particle diameters).The influence rule of the technological parameters of some aluminum powder particles was obtained: Under the premise of guaranteeing the explosive equivalent of the thermobaric explosive,if we increase the mass proportion of the particles in the thermobaric explosive,the detonation performance of the thermobaric explosive would be greatly increased.The particle size reduction can accelerate the particle reaction rate,but due to the amount of energy emitted,the decrease of particle size has little effect on the overpressure of warm-pressed explosives.4,the numerical simulation model and program established will be expanded to the numerical simulation of explosive effect for Dense Inert Metal Explosives(abbreviated DIME,which is a mixture of conventional explosives and inert heavy metal powders),and the preliminary analysis results are obtained,which can explain the low collateral damage characteristics of the explosives.