Theoretical and Numerical Study on Dynamic Response of Propellant Actuator

Abstract

In order to solve the complexity of the structure, assembly process, component contact state and working process of the propellant actuator by conventional methods, a novel design method based on theoretical and numerical analysis was proposed. The internal ballistic model of the propellant actuator was established based on the classical internal ballistic theory, and the pressure–time characteristic curve of the propellant gas was then obtained. According to the characteristic curve, the dynamic characteristics of the piston under different design conditions of the shear slice were calculated by numerical simulation. The results show that the pressure–time characteristics of the internal ballistic model were in good agreement with the experimental data, indicating that the the internal ballistic model of the propellant actuator is reasonable. Additionally, the structure optimization design and drop safety of the propellant actuator were carried out using the finite element method. It was found that with increasing the propellant charge, the movement time of the piston decreases and the maximum velocity increases. Moreover, the critical values of the propellant charge are 5 mg, 6 mg, 7 mg for the thickness of the shear slice of 0.2 mm, 0.3 mm and 0.4 mm, respectively.