基于高压气体驱动的爆炸波模拟激波管冲击波衰减历程控制方法

A control method for attenuation history of shock wave generated by blast simulation shock tube based on high pressure gas driving technic

基于高压气体驱动的爆炸波模拟激波管,一般采用驱动段、喉部、膨胀段的结构形式,可产生特征与爆炸波接近的模拟冲击波,是实验室中开展长正压作用时间爆炸毁伤效应研究的理想平台。通过调整激波管的变截面结构和驱动段形状,实现冲击波超压衰减历程的控制,是此类爆炸波模拟激波管设计面临的核心问题之一。基于实验室现有的爆炸波模拟激波管结构,建立了激波管内一维流动数值计算模型;参考统计学理论,提出了基于决定系数的激波管模拟冲击波与标准爆炸波相似度评价方法;进而以变截面激波管的流动特性为基础,研究了驱动段形状对冲击波衰减历程的影响机理。研究结果表明:采用距离喉部越远、截面直径越小的驱动段形状,以决定系数为量化标准、优化驱动段形状,控制稀疏波、压缩波在激波管内的运动过程,可以获得接近于爆炸波指数衰减特征的模拟冲击波。

A high-pressure-gas-driving blast wave simulation shock tube,commonly composed of driving section,throat section and expansion section,is an ideal platform for explosion damage effect research of long positive shock pressure duration time in the laboratory,as the ability of generating simulated shock wave with similar characteristics to real explosion wave.One of the core problems in the design of blast simulation shock tubes,is the control method of the simulated wave attenuation process by modifying the variable section structure and the driving section shape of the shock tube.In this article,a numerical calculation model of one-dimensional flow in the shock tube is established based on the explosion simulation shock tube in the laboratory,a similarity evaluation method of simulated shock wave and standard explosion wave in a shock tube based on determination coefficient is proposed referring to the statistical theory.Then,based on the flow characteristics of the variable section shock tube,the influence of the shape of the driving section on the shock wave attenuation history is studied.The results show that,it is feasible to acquire simulated wave with approximate exponential attenuation history of real blast wave,by using variable cross-section driving tube,of which the section diameter decreases with the growth of distance to the throat,optimizing the variable cross-section structure due to the determination coefficient,and controlling the motion property of expansion and compression wave in the shock tube.