Numerical study of a novel monolithic heat exchanger for electrothermal space propulsion

Abstract

Fully-coupled multiphysics simulations are applied to investigate a number of candidate heat exchanger materials in the Super-High Temperature Additively-Manufactured Resistojet (STAR) thruster. Two mission applications are considered: a low earth orbit (LEO) primary propulsion application and a secondary reaction control system (RCS) application of an all-electric geostationary (GEO) telecommunications platform. High-temperature operation provides a significant increase in specific impulse over the state-of-the-art Xenon-resistojets. Inconel 718 is investigated for moderate-performance for LEO applications, while pure tantalum and pure rhenium are examined for the extreme temperature high-performance GEO application. Simulations determine the attainable performance including heat transfer, Navier-Stokes continuum flow and Joule heating physics in both transient and steady state. Nozzle efficiency, heat exchanger efficiency, electrical characteristics and other key performance indicators are explored.