Study On Characteristics Of Initiation And Detonation Transfer For Micro-Diamater Charge

Micro miniaturization and smart system direct a way in the explosive trains and it is one of the most important development in the future. Non-ideal detonation phenomena could be appeared in micro-diameter charge, and a new problem also appeared in initiation and detonation transfer. Layer upon layer difficulties appeared in studying explosive trains, the characteristic of initiation and detonation transfer must be studied in the face. In the paper, micro-diameter charge initiation and detonation transfer rule are studied from the perspective of theory, experiment and simulation.(1) The current domestic and international research on theory, experiment and simulation has been summarized in the paper and then the research questions were put forward.(2) Non-ideal detonation in micro-diameter charge was studied, based on the analysis of side rarefaction wave influencing detonation velocity, detonation pressure and wave front. The flow pipe theory and curved front theory are deduced and analyzed; conclusions of specific applicability are obtained.(3)The rule of air gap attenuation detonation pressure was studied on micro-diameter charge constraint condition, thus the experiential relational expressions of JO-9C booster explosive in same density and different diameter charge were obtained in constraint condition of 45# steel or PMMA. The air-gap decaying model of micro-diameter charge detonation wave was obtained. The results indicate that the bigger charge diameter is, the smaller decaying coefficient is. With different air-gap thickness, detonation pressure can be also correspondingly changed. Detonation performance can be controlled by adjusting air-gap thickness.(4) The rule of micro-diameter charge driving flyer was studied on testing flyer velocity by electromagnetic method. 1) The influence rule between flyer material and flyer velocity was studied. The results indicate at the same diameter charge and constraint, the bigger flyer material density is, the smaller flyer velocity is. 2) The influence rule between flyer thickness and flyer velocity was studied. The results indicate at the same diameter charge, constraint and flyer material, the bigger flyer material density is, the smaller flyer velocity is. The position of maximal flyer velocity was forward lead. 3) The influence rule between diameter charge and flyer velocity was studied. The results indicate at the same flyer material, flyer thickness and constraint, the bigger diameter charge is, the bigger flyer velocity is. The position of maximal flyer velocity was forward lead. 4) At the premise of superposition, the next propellant was credibility ignition by adjusting flyer material, flyer thickness and diameter charge. It also supply experiment support and technique guide to credibility ignition and detonation transfer of the micro explosive trains.(5) Air-gap decaying detonation wave transfer calculated models of micro-diameter charge were founded by adopting nonlinear dynamic 3D-finite programming of LS-DYNA, ALE algorithm and constrained Lagrange in solid method in order to simulate the air-gap decaying detonation transfer process for JO-9C booster explosive in micro-scale charge. The numerical simulation results are in accordance with experiments.