Performance Analysis Of Microelectromechanical Thrusters Using A Direct Simulation Monte Carlo Solver
In the present study, a direct simulation Monte Carlo solver is utilized to simulate the effects of heater plates on the performance parameters of microelectromechanical propulsion devices. The simulation is two dimensional. Proper cell dimensions, number of particles per cell, and grid study are used to guarantee the accuracy of simulations. Three types of microthrusters including cold gas as type 1, a propulsion device with heaters in the walls as type 2, and a microthruster with heater plates inside the domain as type 3 are studied. Type 1 is considered as a reference case and two other types are compared with type 1. It is observed that heater plates inside the microelectromechanical thruster enhance the downstream temperature due to conversion of pressure drop occurred by plates into temperature. In type 3, the specific impulse is enhanced but the thrust force is decreased in comparison with type 1. Heating the walls in type 2 accelerates the flow while there is no considerable pressure reduction. Moreover, all performance parameters are increased in this type. It is also demonstrated that increasing of wall temperature increases thrust and specific impulse and decreases the sensitivity of thruster due to rarefaction effects.