Numerical Simulation Of Shock Sensitivity Experiments (SSGT)

Shock sensitivity is an important index that can judge the difficult or easy degree of detonation and detonating performance of explosive. Small scale gap test (SSGT) is one of the most general methods that study shock sensitivity. Owing to consumption of so much manpower and material resources in small scale gap test, SSGT is simulated for making it possible to choose the best experimental programme, and reduce the experimental expenses, and shorten the research periods, and even replace SSGT. Small scale gap test is numerically simulated with LS-DYNA in this paper. The data from several standard shock initiation and HE performance experiments at home and abroad were used to determine the parameters required for the Ignition and Growth model of the acceptor explosive. The two test explosives of HMX/F2641 (90%TMD and 95.5%TMD) and the three test explosives of RDX/F2641 (80%TMD,90%TMD and 95%TMD) are numerically simulated. Compared with the experimental results, the results of numerical simulation show that this calculated model is in accord well with the real process of SSGT. The error of shock sensitivity is within 0.05mm, which is more precise than those reported on documentation at home and abroad. In addition, the different parameters in Ignition and Growth model are adjusted in order to qualitatively examine the influence on shock initiation behavior made by the parameters. According to the initiation research at home and abroad, the improvement in Ignition and Growth model and the application of the model in LS-NYNA are discussed, which provides a good basis for further research about the different effects on the shock sensitivity by particle size of different explosive in numerical simulation.Main conclusions could be reached by numerical simulation and analyses as follows:As can be seen from the results of the numerical simulation, it's possible that the data from several standard shock initiation and HE performance experiments are used to determine the parameters required for the Ignition and Growth model of the acceptor explosive are feasible.This calculated model is in accord well with the real process of shock sensitivity experiments (SSGT). The results of numerical modeling by adjusting the related parameters based on the results of experiments effectively show the details hard to be observed from experiments.By adjusting the parameters of the Ignition and Growth, we can see that the growth terms have a much greater influence on the shock sensitivity than the ignition terms.This research technique in the paper could be used for the design and simulation of detonation initiation and propagation sequence, and also benefit other research related to the similar topic.