Coupling Influence of Chamber Structure's Radial Vibration and Internal Ballistics for Solid Rocket Motor

摘要

Abstract: Influence of radial vibration of the chamber structure including propellant grain and casing on the internal ballistics of solid rocket motor (SRM) was investigated in SRM chamber. In our study, internal ballistic models of SRM are required which incorporate the gas dynamic flow within the motor's core , the propellant burning process at he core periphery and influence of solid structure' radial vibration. For the purposes of this study, it was considered suitable to employ a rapid kinetic burning-rate model as the boundary condition of the core periphery along the propellant grain. The surface regression rate was described by the phenomenological mode, which is a function of pressure, core flow, and acceleration.. According to elasticity theory and vibration mechanics, a simplified ordinary differential equation applies for structural radial vibration due to flow pressure Finally, the interactional of structure radial vibration and the internal ballistics of SRM are occurred by following approach: vibrate of flow pressure will product structure radial vibration; radial vibration displacement will change the radial dilatation of the flow at a given section; radial vibration acceleration will increase the burning-rate, The coupling influence of chamber structure's radial vibration and internal ballistics for solid rocket motor has been illustrated by this numerical study. When pressure of internal ballistics was periodic oscillation, the influence of radial vibration of the structure on the internal ballistics would rise pressure wave amplitude of the chamber structure up to almost ten times.