Simulation Of Work Process Of Soid Micro Thruster

ABSTRACT:Micro-Electro-Mechanical System based solid micro thruster have attracted more and more attention because of its low cost, high reliability advantages. In view of the present simulation study of solid micro thruster, there is no study which considered both solid propellant burning surface regression process and the interaction of propellant gas phase products. This paper propose a way to simulate the solid propellant combustion process with the method of combining the solid propellant burning rate formula and the gas phase chemical kinetics mechanism. In this paper, the main research object is a type of solid micro thruster, propellant by AP/HTPB (Ammonium perchlorate/Hydroxyl-terminated polybutadiene), study the solid propellant combustion, gas flow and heat transfer process with the method of the numerical simulation.The simulation of the working process of solid micro thruster is based on FLUENT software, through solving the propellant burning rate formula, setting up the model of chemical kinetics of the propellant and the fluid solid heat coupling model, establish a complete simulation model of solid micro thruster working process. Then conducted the simulation research of the transient working process of solid micro thruster, obtained the combustion temperature, the pressure of chamber, concentration distribution of each component in micro thruster, gas flow velocity, the Maher number and variation rules of the thrust with time, in order to analyze the propellant combustion and micro thruster’s performance.This paper first studied the AP/HTPB propellant mass ratio, analyzes the rules of combustion temperature and concentration distribution of each component in micro thruster, study the gas phase interaction mechanism between each other with different ratio of propellant. Then we study the influence law on propellant combustion and micro thruster performance with different solid micro thruster’s wall conditions (wall materials and wall thickness) and structural parameters (chamber diameter and nozzle expansion half angle), deeply analyzed and explained the influence rules of various phenomena of solid mciro thruster in working process and parameters to the working process of solid micro thruster.