Numerical Method of Propulsion Concept: Partially Cut Multiaperture Stick Propellant

Abstract

The partially cut Multiaperture stick propellant is a new concept charging structure. In this paper, in order to accurately obtain the change and development process of the two-phase flow field in different stages of the whole interior ballistic process in this propulsion concept system, a coupled calculation model of computational interior ballistic is established, which converts the Euler-Lagrange method to the Euler-Euler method. Firstly, at the initial stage of ignition, the Euler-Lagrange method is used to describe the flow field. During this period, the gas phase is based on Euler coordinates, while the solid phase is based on Lagrangian coordinates. After the projectile starts, the partially cut Multiaperture stick propellant is fractured into granular propellant. The flow field is converted to describe by the Euler-Euler method by using the initial mapping method. Finally, by comparing the calculated results with the experimental results, the maximum pressure error is only 0.54%, which verifies the accuracy and effectiveness of the coupling calculation method. It effectively captures the distribution of the physical parameters in the combustion chamber, providing a new research method for the computational interior ballistic of the propulsion concept. Based on this method, the pressure distribution in the propulsion concept system is obtained, and no obvious shock waves and expansion waves are seen, indicating that the charge scheme of partially cut Multiaperture stick propellant can improve launch safety.