Satellite & Space Missions

Biography

Biography: Reuben Jikeme Umunna

Abstract

A resist-o-jet is an electrically heated thruster wherein electric energy is converted to thermal energy by Joule-heating for the purpose of raising propellant temperature. Resist-o-jet thrusters have been extensively studied since the 1960’s as a cheap and reliable performance enhancement for spacecraft translations. This work aimed to design a low power heat exchange to be used in a cold gas or liquefied gas satellite propulsion system. The design ensures complete vaporization of the propellant (if liquid) within the thruster chamber and improves the specific impulse of the thruster. To maximize heat transfer, various heat exchanger configurations were studied in detail. These studies revealed that two different heating methods exist - indirect and direct heating. The indirect heating method requires a heater and an exchanger thus, making it difficult to isolate the propellant from having direct contact with the heater. The direct method on the other hand combines both functions in a single element where the propellant makes direct contact with the heater, allowing for a relatively simple and more reliable design. This work outlines the design process of a 50watts direct contact heating resist-o-jet thruster.