Design and testing of additively manufactured high-efficiency resistojet on hydrogen propellant

Introduction to the Study

Article Overview

Authors: Giulio Coral, Kiyoshi Kinefuchi, Daisuke Nakata, Ryudo Tsukizaki, Kazutaka Nishiyama, Hitoshi Kuninaka.Institutions:

• The University of Tokyo

• Nagoya University

• Muroran Institute of Technology

• Japan Aerospace Exploration Agency (JAXA)Keywords: Additive manufacturing, Resistojet, Electrothermal propulsion, Hydrogen

Abstract

This study focuses on the design and performance testing of an additively manufactured resistojet utilizing hydrogen as a propellant, aimed at achieving high performance in space propulsion systems. It addresses the advantages of additive manufacturing techniques in producing reliable and efficient thrusters that are well-suited for the demands of modern aerospace applications.The design methodology is elaborated upon, particularly emphasizing a simplified thermal design approach for the engineering of resistors fabricated from Inconel 718 and tungsten. This is critical for managing the high temperatures associated with propulsion systems. The experimental testing has yielded a remarkable peak thermal efficiency of 96%, which not only validates the proposed methodology but also showcases the effectiveness of the chosen materials under operational conditions. Furthermore, the potential application of the resistojet for high specific impulse (Isp) orbit transfers is proposed, particularly in conjunction with advanced cryogenic storage technologies, enhancing mission capabilities in spacecraft design.

Fine Points about High Δv Maneuvers

Understanding high Δv maneuvers, such as Geostationary Transfer Orbit to Geostationary Orbit (GTO-GEO) transfers, is paramount in contemporary space missions. These maneuvers necessitate careful consideration of the balance between transfer time and launch mass. Traditional chemical propulsion systems, like those based on MMH/MON-3 propellants, often impose steep mass penalties, subsequently elevating launch costs. On the other hand, alternative propulsion systems, specifically electric propulsion using Hall thrusters, present a solution by reducing launch mass but introduce extended transfer durations, typically spanning 4 to 6 months.Notably, electrothermal thrusters employing hydrogen promise a revolutionary advantage by potentially minimizing both mass and transfer time, enhancing mission efficiency with an Isp exceeding 800 seconds, thus representing a significant advancement in propulsion technology.