Discussion on Stirling or "hot air" engines (all types)
1 post • Page 1 of 1
http://www.newscientist.com/article/dn3 ... ngine.html
The putt putt boat is probably one of simplist heat engines with no moving parts. It can be made out of drinking straws and a pop can at its most basic. The engine can be improved. It has two cycles steam explosion in a flash boiler ,followed by an implosion of the condensing steam. This causes the engine to jerk back and forth, even though it progresses forward. This can be solved with a reed valve. You can also add an effector nozzle at the end of the exhaust pipe. It just stands off the pipe to let more water be suck in and around it. It works like an air multiplier.
Now hopefully your asking the question I have been trying to lead you to. Can this baby be scaled up? The answer is yes. You can make a pretty fast boat motor with several modifications. They tried to power a boat by using steam straight from the boiler. The steam condenses right behind the nozzle, it doesnt work. The pulsed jet steam engine uses this condensation to draw water and air through the engine.