Mathematical Model and Numerical Simulation of Two-Phase Flow Interior Ballistics of Variable Burning-Rate Propellant

In order to describe the combustion and interior ballistics processes of variable burning-rate propellant more accurately, the model of two-phase flow interior ballistics of variable burning-rate propellant is established, which consists of one center hole and double layers. In the charge condition of 30 mm cannon, Lax-Wendroff difference scheme with second order accuracy is used to get the numerical solutions of the model. The pressure and velocity profiles calculated are in good accordance with the actual ones. Therefore this numerical model can truly and accurately reflect the real physical process of interior ballistics. The simulation results show that it is very effective to restrain the pressure waves in the bore of variable burning-rate propellant, which is great benefit for fire safety. The analysis of the calculation parameters, such as phase velocity and bore pressure, plays a guiding role in the further research of the interior ballistics process of variable burning-rate propellant.