Material selection based on joule heating simulation for resistojet thruster

Abstract

Resistojets generate heat by passing an electric current through a resistive element, thereby heating a propellant at high pressure, which is subsequently expanded through a nozzle resulting in a supersonic exhaust jet. Specific impulse of a resistojet decides the performance of the thruster. Hence the goal here is to achieve highest specific impulse. The specific impulse of the resistojet is limited by the thermal design of the heater and the material selection. Since the design specifications on the resistojet model has been confirmed with calculated data points obtained from literature work, the material selection is done with the heat transfer simulation. Also, the materials selected as the simulation model is done on accordance with highest melting point and the factor of feasibility is taken into account. For achieving the heat transfer distributions among the flow channels through conduction allows the calculation of heat flux along the radial direction. The transient state condition of the turbulent fluid region is solved under the CFX solver. The simulation is done on different materials varying their thermophysical properties. The end result will be decided on the basis of the heat transfer rate and the residual obtained during higher iterations. Thus, this paper focuses on the choice of materials and the thermal analysis of the same to achieve the highest specific impulse and an efficient performance output.