Hello guys, I'm new here but I see you are discussing Brayton and I know some things about the engine posted above... It was proposed by Richard Proschell of Pro power systems... He was never able to make a working version of the engine. There are some early engines that have a piston and expander with heat added in between but they are usually large engines and they make little power... true Brayton engines on the other hand are actually combusting in the expansion cylinder. There is a big difference between a Brayton engine and engines of this type. I have made several Brayton type engines over the last 15 years .. here is one of my latest engines.
https://www.youtube.com/watch?v=wlTfwrLiJ0E here is an engine which adds heat between a compressor and expander...
https://www.youtube.com/watch?v=lbYvlBrRjmQ
