高压气体驱动激波管的数值模拟与参数影响分析

Numerical Simulation and Parametric Analysis of High-Pressure Gas-Driven Shock Tube

爆炸荷载作用下建筑构件的动态响应与损伤破坏的试验研究对于结构抗爆设计具有重要的参考价值。为了探究激波管参数对末端荷载峰值和持时的影响,首先,基于商用有限元分析软件ANSYS/LS-DYNA开展了典型激波管试验的数值模拟,通过对比膨胀段末端反射超压和测试构件的挠度时程,验证了激波管有限元模型、参数取值和数值分析方法的准确性;然后,设计了末端尺寸为3 m×3 m的激波管,开展了激波管几何参数和驱动段超压对末端反射超压的参数影响分析,结果表明:超压峰值和持时随驱动段长度、直径和超压的增大而增加,随膨胀段角度减小而增加;最后,给出了基于反射超压峰值和持时的激波管设计方法,并通过设计算例进行了验证。

It has great importance for the blast-resistant design of the structures to study the dynamic response and damage failure of structural components under explosion loads.This work focused on analyzing the influences of the shock tube's parameters on the loads at the end of the driven section.Based on the ANSYS/LS-DYNA,the numerical simulation of the shock tube is conducted.The accuracy of the finite element model,parameters values,and the numerical simulation method are verified by comparing the numerical simulation results,such as overpressure-time histories and the deflection response of the reinforced concrete slabs,with the experimental results.Furthermore,a shock tube with a size of 3 m×3 m at the end of the driven section is designed.The influences of the shock tube's geometric parameters and its inner overpressure on the loads at the end of the driven section are analyzed.The results show that the peak overpressure and positive time duration increased with the increase of the length,diameter,and pressure of the driver section.The results also show that the peak overpressure and positive time duration increased with the decrease of the angle of the expansion section.Finally,the design method of the shock tube based on peak overpressure and positive time duration is given,which was verified by the designed examples.