[Gasification] Intermittent Combustion

[Bob Stuart]

Happy New Year, everyone.
I have a fascinating new puzzle that began with contemplation of the  
Humpfrey pump, and general frustration over the lack of free-piston  
heat pumps on any fuel.  Given the abilities of tuned pipes, it might  
be possible to dispense with even liquid as a piston.
The basic notion is just this: Rather than extract combustible gasses  
for use in an IC engine, put solid fuel into the combustion chamber,  
but time the injection of high-pressure air to burn it, creating  
power pulses.  There are hundreds of ways to achieve this, and a re- 
fueling mechanism to invent, but I see a lot of potential for overall  
simplification.  Maybe a single log can be slowly fed in as the  
cylinder head surface.  Even a common airtight stove might get  
modified to make useful pulses.
Thoughts?

Bob Stuart