Are they the thermoacoustic engines new generations? Maybe!
What is the aim?
The engine can be simple, , light (in parabolic mirror) cheap, and easily to build (by amateurs or anybody).
The engine must be only from tubes, that we can easily put it under pressure.
100 Watt category.
This engines are base the diaphragm and piston system:
Make a diaphragm:
Make a piston:
I think that these engines have two main groups. The bypass and loop engines.
When displacer piston and diaphragm are close then this engie rather works same than a bypass engine. When they are far then it is rather a loop engine.
"1" type is better than "2". Diaphragm and piston are near.
Diaphragm and piston between is the power piston.
This engine is much better, than traditional stirling fluidyne engine
This works also, but not so good, moreover, here is moisture condensation too.: