Microwave Electrothermal Thrusters

[Michel Van]

The Idea is simple a Magnetron heat up liquid into a flowing gas or even Plasma

first prototype using water had ISP around 800 sec

more on that

Microwave Electrothermal Thruster | Electric Propulsion and Plasma Dynamics Laboratory

alfven.princeton.edu

PDF:

https://www.researchgate.net/publication/3166116_The_microwave_electro-thermal_MET_thruster_using_water_vapor_propellant

https://etda.libraries.psu.edu/files/final_submissions/1358

http://erps.spacegrant.org/uploads/images/images/iepc_articledownload_1988-2007/1993index/IEPC1993-036.pdf

 

[Kevin Renner]

Could this be scaled up

 

[Dragon029]

Theoretically yes, but you'd very rapidly run into constraints with the amount of electrical power required; realistically you'd want to only use this technology for low-thrust applications like for satellite station-keeping, or perhaps slow manoeuvres for vehicles operating far from Earth. Ion / plasma thrusters offer even higher ISPs, but they have the disadvantage of requiring things like noble gases, whereas for interplanetary vessels looking to get refueled away from Earth it'll be a lot easier to collect water than (eg) xenon.

 

[edwest4]

This can be scaled up and water can be used.

The microwave electro-thermal (MET) thruster using water vapor propellant

The research to develop the microwave electro-thermal (MET) thruster at Research Support Instruments, Inc. (RSI) using a variety of gases as fuel is described. The MET has undergone dramatic evolution since its first inception, and it is now moving toward flight development. The MET uses an...

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