Shock Response Characteristics and Unreacted Equation of State Calibration of GAP/RDX/TEGDN propellant

Understanding the shock response characteristics of propellants is crucial for studying the safety of the shock wave dominating shock initiation. To study shock response characteristics of high-energy solid propellant (GAP/RDX/TEGDN propellant, GRT propellant) and obtain its unreacted equation of state (EOS) parameters, a shock response experiment (plate impact experiment) was conducted using a caliber 57 mm single stage light-gas gun device. The propellant/window interface particle velocity is measured by using a velocity interferometer system for any reflector (VISAR), and the corresponding mechanical parameters of GRT propellant are obtained by the impedance matching method. The Hugoniot parameters of GRT propellant further were obtained by the parameter inversion method based on Abaqus/explicit, calibrated the unreacted EOS. The experiment results show that: At an impact velocity of 212 m·s^-1 and 282 m·s^-1, the propellant/window interface particle velocity time-history curve shows a double wave composed of elasticity and viscoplasticity. The shock front rise time in the viscoplasticity wave stage is relatively slow and shows shock viscosity characteristics. The shock viscosity is attributed to the viscous dissipation of each constituent and the wave scattering caused by a wave impedance mismatch between each constituent. Its duration decreases with impact velocity increasing. In addition, the unreacted EOS fitting curve is consistent with the experimental result inversion value and the calibrated parameters are valid.