光子多普勒测速仪与压杆相结合的冲击波反射压力测试技术

摘要

A pressure measuring system with combining pressure bar with photonic Doppler velocimeter (PDV) is developed for measuring the reflected blast wave pressure in strong electromagnetic interference environment.The axial velocity of PDV probe is eliminated by mounting it in a sliding structure.The velocity curve of bar's rear surface has many peaks on it due to the multiple reflection of elastic wave in the bar.The velocity of elastic wave is obtained by fitting the takeoff points of the curve.The system response characteristics,effective measuring time and minimum measured pressure are analyzed.The system has been successfully used to measure the reflected blast wave pressure of spherical explosive.The results show that the response of the proposed system is lower than that of strain measuring system,and the minimum measured pressure of the proposed system is better than that of strain measuring system.The maximum pressure of explosion shock wave of spherical explosive is 463.5 MPa with rising edge of 5 μs.This research illustrates that the measuring technique based on pressure bar and PDV is feasible.%为在强电磁干扰环境下测量爆炸冲击波的壁面反射压力,将光子多普勒测速仪(PDV)与压杆相结合,设计了一套压力测试系统.采用滑动安装结构消除探头在应力波作用下产生的轴向速度,根据杆中弹性波多次反射的压杆自由面速度曲线,提取起跳点,拟合得到了压杆声速.对压力测试系统进行了响应特性、有效测量时间和测量下限分析,并采用该系统测量了球形炸药爆炸的冲击波反射压力.研究结果表明:该系统频响低于杆表面粘贴的应变片电测系统,测量下限优于应变片电测系统;测得的球形炸药爆炸的冲击波最大反射压力为463.5 MPa,上升沿为5μs;PDV和压杆相结合的冲击波壁面反射压力测试技术可行.