Jet propulsion by microwave air plasma in the atmosphere: AIP Advances: Vol 10, No 5

We propose a prototype design of a propulsion thruster that utilizes air plasma induced by microwave ionization. Such a jet engine simply uses only air and electricity to produce high temperature and pressurized plasma for jet propulsion. We used a home-made device to measure the lifting force and jet pressure at various settings of microwave power and the air flow rate. We demonstrated that, given the same power consumption, its propulsion pressure is comparable to that of conventional airplane jet engines using fossil fuels. Therefore, such a carbon-emission free thruster could potentially be used as a jet thruster in the atmosphere.

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n this report, we consider a microwave air plasma jet thruster using high-temperature and high-pressure plasma generated by a 2.45 GHz microwave ionization chamber for injected pressurized air. We propose a simple prototype plasma jet thruster that can generate approximately 10 N of thrust at 400 W using 0.5 l/s for the airflow, corresponding to the lifting force of 28 N/kW and a jet pressure of 2.4 × 104 N/m2. At a higher microwave power or greater airflow, propulsion forces and jet pressures comparable to those of commercial airplane jet engines can be achieved.

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When high-power microwave is generated using microwave sources arranged in parallel, higher heat is also generated. At this time, the method of measuring the propulsive force with a steel ball is no longer applicable. How to deal with the impact of high temperature on equipment and how to evaluate the driving force are challenges that require further research

Source: Jet propulsion by microwave air plasma in the atmosphere: AIP Advances: Vol 10, No 5