The National Nature Science Foundation of China, No.11272081,2013.1-2015.12
Xiaojie LI
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 under water shock wave of massive charged explosion.