Study And Simulation The Large Scale Gaps Test Of Aluminized Explosives

The shock wave sensitivity of explosives is the method of evaluating the degreeof difficulty of explosives impacted by the shock wave, in general is presented bycritical gap thickness or critical initiation pressure. In this paper large scale gaps test(LSGT) is used to evaluate the shock wave sensitivity of aluminized explosives. Andto study the shock wave sensitivities of aluminized explosives and the shock pressurein this experiment, there are three methods - theory, experiment and numericalsimulation have been used.The pressure and velocity of shock wave which produced by donor explosive—insensitivity RDX impacting vertically the interface of aluminum gaps can beobtained by theoretical calculation. And these parameters are considered as the initialparameters of process of the shock wave attenuated by aluminum gaps. Then thepaper supposes that the process of attenuation is a one-dimensional and isentropicprocess and rarefaction wave is the only factor during this process. It gets theattenuation rule that the shock wave pressure produced by donor explosiveinsensitivity RDX attenuate through different gaps with exponential. The paperapplies the program ANSYS/LS-DYNA to simulate the LSGT of 6% and 30%aluminized explosives, and according to the trend of pressure to judge the explosive isdetonation or not, at last, gives their critical gap thickness is 33.75mm and 28.75mm.At the same time a attenuation empirical model of shock wave produced byinsensitivity RDX is found by means of experiment.For experiments of LSTG the only judgment is the depredation on steelappraisal. And the paper obtain the critical gap thickness of 6% and 30% aluminizedexplosives is 31.61mm and 27.47mm. Compared with the result of simulation, theirpercentage errors are 6.77% and 4.66%. The result proves that the material parametersand numerical model are right during simulating LSGT, and this method couldprovide more reference for tset subsequent.