炸药爆轰状态方程参数的水下爆炸测试方法研究

Equation of state (EOS) for explosives is one of basic subjects in explosive mechanics and explosion physics. Currently, test techniques for determining parameters of explosive EOS is very complex, as a result, explosive EOS parameters are very difficult in searches. Therefore, a measurement, based on the underwater explosion of spherical explosives, was proposed to determine EOS parameters of massive charged explosives. The main test process is to measure the path line of near-field shock-wave-front caused by a spherical underwater explosion, and invert the EOS's parameters according to the wave-front trace. There are three main parts in this proposal, including test technique, inversion theory, error theoretical analysis and control technique. First, in order to record the trace of underwater shock-wave-front, a continuous resistance wire sensor need to be used in test. Therefore, the sensor element of continuous resistance wire, worked under high pressure, is one of key techniques. So a pressure-sensitive conductive coating will be selected out and prepared as wirelike sensitive element. The second step is the inversion analysis of underwater explosion. the reverse solution of these characteristic curves of non-isentropic flow (non-uniform-entropy flow) will be deduced, combined with the parameter optimization method, to solve the detonation pressure and EOS's parameters of explosives from the attenuation data of underwater shock wave. An auxiliary test method will be introduced to deal with the mismatch problem of interfacial acoustic impedance between water and explosives. The influence of auxiliary test and the interface max between water and gas will be calculated by 3D FEM and meshless method. The calculations can ascertain the order of magnitude on error. The test technology can be used to mensurate the EOS's parameters, what's more, it is also a complementary tool in the research of detonation pressure testing and the near-field udderwater shock wave of massive charged explosion.

针对目前炸药状态方程参数缺乏，状态方程测试方法复杂的问题，本项目拟研究一种适用于大炸药量的爆轰状态方程测试技术。主要是通过测取水下球型炸药的近场冲击波，根据冲击波衰减规律反演出炸药状态方程参数。项目的研究主要包括测试技术、反演理论、误差控制技术与理论分析三个方面。测试技术采用连续电阻丝测试的方法，连续测出水下冲击波的迹线，因此需研究制备连续电阻丝传感元件，采取压致导电涂层的方法解决。对于水下爆炸的反演，研究非均熵流的特征线逆解法，与参数优化方法相结合，由冲击波衰减规律直接反演求解出炸药爆轰压力与状态方程参数。对水介质与炸药声阻抗失配等问题，用辅助测试方法解决，并利用三维有限元和无网格方法计算辅助测试、气-水界面混合等对水下冲击波的影响，从理论上确定误差量级。拟研究的试验方法不仅可以用于炸药状态方程参数测试，同时也是大药量水下爆炸近场冲击波测试的一种补充研究手段。

针对目前炸药状态方程参数缺乏，状态方程测试方法复杂的问题，本项目研究了一种测量炸药爆轰状态方程方法。主要是通过测取水下球型炸药的近场冲击波，根据水下冲击波衰减规律反演炸药状态方程。项目的研究主要包括野外测试技术、反演理论两个部分。测试技术采用连续电阻丝测试的方法，连续测出炸药爆轰和水下冲击波的迹线。炸药状态方程反演主要采用特征线逆解法与参数优化方法相结合，由水下冲击波边界直接反演出炸药爆轰压力与状态方程。在理论研究方面，项目发展了通用状态方程的非等熵可压缩流特征线解法，以及对应的逆解法，该解法同样适用于二维定常非等熵可压缩流研究。由于阐明了非等熵可压缩流中特征线的物理实质，该方法也可以用于求解非理想炸药爆轰问题，以及非均匀梯度介质中冲击波的传播问题。在测试技术上，项目发明了新的连续电阻丝压导传感器，开发了高频响的连续电阻测试仪，以及一系列的爆炸实验测试方法。不仅可用于一维球型水下爆炸，已经开始用于柱状装药水下爆炸，炮孔中炸药爆速与爆压联测，工业炸药性能测试，以及爆炸加工等方面。