Research on the MET (Microwave Electro-Thermal) Thruster Using Water Vapor Propellant

Dr. John Brandenburg
Friday, November 4, 2005
1:30PM - ENG II 102

Abstract


The research effort to develop the MET (Microwave Electro-Thermal) thruster using a variety of gases as propellant is described with emphasis on recent research conducted at FSI (Florida Space Institute) under contract to DARPA (Defense Advanced Research Products Administration). The MET has undergone dramatic evolution since its first inception, and it is now moving towards flight development. The MET uses an electrodeless, vortex-stabilized microwave discharge to superheat gas for propulsion. In its simplest design, the MET uses a directly driven resonant cavity empty of anything except gaseous propellant and the microwave fields that heat it. It is a robust, simple, inexpensive thruster with high efficiency, and has been scaled successfully to operate at 100W, 1kW, and 50kW using 7.5, 2.45 and 0.915GHz microwaves respectively. The 50KW, 0.915GHz test was perhaps the highest power demonstration of any steady state Electric thruster. The MET can use a variety of gases for fuel but the use of water vapor has been shown to give superior performance, with a measured specific impulse (Isp) of greater than 800 s. When this added to the safety, ease of storage and transfer, and wide availability of water in space, the potential exists for using a water-fueled MET as the core propulsion system for refuelable space platforms.

Short Bio


John E. Brandenburg is a visiting professor researcher at (FSI) Florida Space Institute having come from The Aerospace Corporation. At FSI one of his duties is as principle investigator of the MET (Microwave Electro-Thermal) propulsion project performed under a grant from Defense Advanced Research Projects Administration. He has focused his career on plasma physics and its applications to space and energy problems. He has, in addition to being involved in several Mars mission planning activities, published several papers on past Mars climate and possible biology. He also performed research on Fusion Propulsion and Kaluza-Klein theory of Field Unification for purposes of space propulsion. Before coming to Aerospace Corporation Dr. Brandenburg was a researcher at Research Support Instruments (RSI) where he specialized in making controlled laboratory plasmas for uses ranging from Fusion research to the MET thruster. He also worked as an independent consultant on Space Missile Defense, Directed Energy Weapons, and space rocket plume phenomenology, and also at Mission Research Corporation and Sandia National Laboratories on plasmas for controlled fusion and similar topics.

Doctor Brandenburg was born in Rouchester Minnesota but grew up in Medford Oregon. He obtained a BA in Physics from Southern Oregon University in Ashland Oregon, home of the Shakespearean Festival. He obtained his MS in Applied Science at University of California at Davis and his PhD in Theoretical Plasma Physics at the UC Davis extension campus at Lawrence Livermore National Laboratory in Livermore California. The Title of his Thesis was .A Theoretical Model of a Reversed Field Ion Layer Made of Monoenergetic Ions. and dealt with the magnetic confinement of plasmas for controlled nuclear fusion. Inspired by the Apollo missions to choose a career in Physics he has always been an avid fan of space exploration and science fiction. He is the author the .Dead Mars, Dying Earth. with Monica Rix Paxson , and, which dealt with the problems of energy and global warming. He has had published a space oriented science fiction novel . Morningstar Pass: The Collapse of the UFO Coverup. . under the pen name of Victor Norgarde.