Electric microwave plasma thruster could rival traditional jet engines
A Chinese team has demonstrated a prototype of a microwave plasma thruster capable of working in the Earth's atmosphere and producing thrust with an efficiency comparable to the jet engines you'd find on modern airliners – under laboratory conditions.
Plasma thrusters are already operational on spacecraft as a means of solar-electric locomotion, using xenon plasma, but such things are no use in the Earth's atmosphere, as accelerated xenon ions lose most of their thrust force to friction against the air. Not to mention, they only make a small amount of thrust in the first place.
This design, conceived and built by a team at the Institute of Technical Sciences atWuhanUniversity, uses only air and electricity, and appears to produce an impressive push that may see it become relevant to electric aircraft applications.
The device works by ionizing air to create a low-temperature plasma, which is blown up a tube by an air compressor. Part way up the tube, the plasma is hit with a powerful microwave, which shakes the ions in the plasma about violently, crashing them against other non-ionized atoms and vastly increasing the temperature and pressure of the plasma. This temperature and pressure generates significant thrust up the tube.
Sauces:
https://newatlas.com/aircraft/microwave-air-plasma-thruster/
https://phys.org/news/2020-05-fossil-fuel-free-jet-propulsion-air.html
https://www.upi.com/Science_News/2020/05/06/Scientists-unveil-fossil-fuel-free-jet-propulsion-that-uses-microwave-air-plasmas/2621588762079/
https://www.dailymail.co.uk/sciencetech/article-8292353/Scientists-design-plasma-powered-jet-propulsion-system.html
https://www.science20.com/news_staff/a_wuhan_lab_develope_fossil_fuelfree_jet_propulsion_using_air_plasmas-247737
https://www.siliconrepublic.com/machines/experimental-plasma-jet-thruster-air-and-electricity
https://www.tasnimnews.com/en/news/2020/05/06/2258595/researchers-develop-emissions-free-jet-propulsion-with-air-plasmas
https://www.theengineer.co.uk/plasma-jet-microwave-wuhan/
https://youtu.be/oqXyX2dUaYA