Monday, July 5, 2010
A Dandy Use for Hot Air -- Stirling Engines
"A Stirling engine is a heat engine that operates by cyclic compression and expansion of air or other gas, the working fluid, at different temperature levels such that there is a net conversion of heat energy to mechanical work. - WikiPedia
These fascinating contraptions have been in existence since 1816, invented by Robert Stirling; they were widely known generically as 'hot air engines' until 1945.
The simplicity, quiet operation, and efficiency of the invention made it popular in the 19th century to early 20th century for uses such as pumping water from the ground for homes and providing air for church pipe organs.
Today, their efficiency and the fact that the engine can run on almost any source of heat (solar, geothermal, biological, nuclear sources or waste heat from industrial processes) seems to have attracted the attention of proponents of renewable energy sources as well as other energy interests.
Where can I get one of these stupendous samples of steam-ish science, you ask?
Purchase a small Stirling engine for 125 GBP at Maidstone Engineering.
Alternatively, if you would rather try to make a Stirling engine from scratch, do take a gander at the creations and instructions by this inventor.
There are as many styles of engines and ways of building them as there are makers, but the basic instructions provided at these links should help get you started in making an engine, or at least in understanding the processes involved:
How to build Jan Ridders' new simple low temperature differential Stirling Engine
A Materials List for Jan Ridders' Stirling Engine
These are just a few of the many fascinating videos and sites dedicated to these compact wonders of early technology. If you build one, please join and post a link to your creation.