Numerical Simulation And Experimental Reserch On Propagation Characteristics Of Blast Shock Wave At Plateau Environment

This paper mainly studies propagation law of explosive shock wave at different altitudes.Based on the characteristic of one dimensional spherical explosive shock wave,the variation law of air shock wave's propagation is analyzed.According to the cloud burst formula proposed by ?.?.???????,the variation law of air shock wave's parameters such as overpressure,positive pressure impulse,positive time,dynamic pressure impulse at different altitudes are derived and compared,in which the influence degree of propagation characteristics of blast shock wave is given quantitatively.The calculated results show that the overpressure of the shock wave decreases with increasing of altitude,meanwhile,the decreasing degree of overpressure is aggravated.The positive pressure impulse decreases with increasing of altitude,and the decreasing rate is almost identical with increasing of the distance.The dynamic pressure impulse of shock wave increases with increasing of altitude.Positive time has little difference in the near field,but it increases with increasing altitude in the far field.When the altitude is fixed,positive time promotes with increasing of distance.Compared and analyzed between static explosion test and theoretical value of modified formula from 200m to 4500m,it supports experimental data for the change rules of the shock wave damage element at different altitudes,which proves the importance of the plateau effect on the blast shock wave's propagation characteristics.At the same time,LS-DYNA and AUTO-DYN numerical simulation software is used to restore explosion test scene,it reconstructed the whole process of the spherical explosion shock wave's propagation at different altitudes.From the numerical simulation results,the flow around the shock wave,corner effect,mach reflection and other physical phenomena are observed.The comparison of static explosion test and simulation results shows the effectiveness of numerical simulation,which further improves the persuasion of the plateau propagation characteristics of shock wave.The research of this problem has important significance on explosive protection and utilization.