Tube Explosive Solid Rocket Motor Combustion Chamber Vibration And Interior Ballistics

Solid rocket motors are subjected on occasion to strong oscillatory axial and radial acceleration environments. The structure vibration can play an important role in influencing the inner flows field and the burning rate of the propellant. The coupling of structural vibration with the internal ballistic of a cylindrical-grain solid rocket motor is investigated through numerical simulation.The structural vibration of solid rocket motors causes great changes of the inner flows field, thus burning rate of the propellant and flow condition of gas changes greatly, and the traditional internal ballistic equations become inapplicable. Therefore, with considering the effect due to structural vibration, one-dimensional nonsteady internal ballistic equations are built through investigate the influence of the structural vibration and refer to the traditional one-dimensional nonsteady internal ballistic equations, In addition, a burning rate model with considering the acceleration effects is introduced because vibration acceleration influences the burning rate obviously.The structure and load of a cylindrical-grain solid rocket motor chamber is symmetrical, which is sufficient used during the process of building the structural vibration model of solid rocket motor. According to elasticity theory and vibration mechanics, a simplified ordinary differential equation applies for structural radial vibration due to flow pressure. The nonrigid axial vibration model of the chamber can be simplified as a longitudinal vibration model of the damping elastic beam.The interaction of structural vibration and the internal ballistics of solid rocket motor is analyzed and the influence of vibration of the structure on the internal ballistics are found. The numerical model predicts that both axial and radial vibration can result in a limited pressure wave strength. The relationship among structural vibration mechanism, burning mechanism and gas dynamic mechanism is compactness. It is conceded that structural vibrations of solid rocket motor can strength the nonsteady internal ballistic behavior.