This is a model of a Stirling engine. The commercial ones are used for a number of purposes but a common use is in combined heat and power (CHP) boiler for central heating. A lot of heat from a standard central heating boiler goes out of the flue to keep the birds warm. A CHP boiler uses this wasted heat to power a Stirling engine (as in the video) which drives an electrical generator the output of which is used to supplement the electricity supply in the building thus cutting electricity bills. Check it out.
Watch video of Flame Gulping Engine submitted by Saba on Oct 29, 2013. This video of Flame Gulping Engine has total 4785 (four thousand seven hundred and eighty-five) Views on Flame Gulping Engine.