Liquid Piston inside-out rotary has 5x greater power density and
specific power vs. piston diesel engine while running on multiple fuels!

Sources & Credits:
Original Rotary
   • Umlaufmotor. Aufbau und Funktionsweise.  

Kurt Roberson
   • Kurt Robertson explains how a Rotary ...  

Felix Wankel
https://www.britannica.com/biography/...

Other Rotaries
   • Wankel animation  
   • Suzuki Re5  
https://www.mazda.ca/en/vehicles/mx-3...

Liquid Piston
https://www.liquidpiston.com/
https://news.mit.edu/2014/liquidpisto...