Stirling

Stirling Cycle engines like their cousins the Steam Engine and Internal Combustion Engines are heat engines in that they use heat to produce working power. They are different in that they do not directly burn fuel to produce that working power. The Stirling engine usually is a two piston arrangement, or more correctly one piston and one displacer. The engine usually consists of a pair of cylinders, one small and one large which are interconnected. The power piston is in the small cylinder and is mechanically linked to the displacer in the large cylinder. The engine works by first heating the air trapped within the power cylinder expanding it forcing the power piston out. The trapped air transfers into the displacer cylinder where it is cooled and contracts, as it contracts the displacer piston and power piston are sucked back in. The air transfers back into the heated chamber where the process starts again. Note that the key is not the heat, the key is the temperature differential between the two cylinders, you can chill the displacer side of the engine and have it work just as well as if you heated the power side. For more detail see Operation Simply Explained In the last century stirling cycle engines predominantly found fame as quiet pumping engines for houses. With a small amount of coal they could keep water pumping all day. More recently the world has been turning to stirling cycle for a more efficient way to power generators and cars. There are some engines in commercial production at present capable of doing this. Of course like the electric car, the stirling car will be a slow accelerating beast.

NAMES Tin Can Stirling Heat Engine
This one is brilliant! Have you been looking for a simple stirling engine to make without much in the way of machining skills? The instructions do call for a metal lathe, but the only part where this is truly necessary is the power piston - if you're lucky in your choice of materials you might be able to find brass stock which fits well enough inside a tube that you could do it without the lathe.



The North American Model Engineering Society (NAMES) has kindly granted permission to publish their instructions to build the NAMES Tin Can Stirling Heat Engine. Dennis Dalla-Vicenza received the the original paper instructions from a NAMES member who picked them up as a convention hand-out. Dennis has converted the document into electronic form as a PDF (Portable Document Format) file. Thanks to Dennis and NAMES (specifically Tom Stockton and Lori Niemuth) we can now all share this novel and easy to build engine design and see the Stirling Prinicpals in action.

The following text is extracted from the instructions...

This project will change your grocery shopping. The use of tin cans simplify construction. The this sheet metal walls permit rapid transfer of heat. The cans are readily modified, and if you go wrong throw the can away and use another.

This engine is not going to be pretty, but it is relatively simple to build and you will come to realize the whole design can be modified in many ways.

Special tools and equipment needed:
  • Metal Lathe
  • 250 watt electric soldering iron
  • propane (or whatever your local gas is) torch
  • 50/50 solder
  • silver solder and flux…

Read more: NAMES Tin Can Stirling Heat Engine

The Ecorun 2.0 Stirling Engine Kit Build Log

The Ecorun 2.0 Stirling Engine Kit is from Exergia – Ideas for Light & Energy by Thomas Shmidt. Available through www.newenergyshop.com

 

This is a blow by blow documentary of the building of a Ecrorun 2.0 Stirling Engine Kit. The article is both the way I built the engine and has the potential to be helpful to anyone building the engine who might need some more information than that given in the good instructions.…

Read more: The Ecorun 2.0 Stirling Engine Kit Build Log

The Ecorun 2.0 Stirling Engine Kit Product Review

The Ecorun 2.0 Stirling Engine Kit is from Exergia – Ideas for Light & Energy by Thomas Shmidt. Available through www.newenergyshop.com

 

It took me about 2 hours to build this wonderful little engine from opening the box through to running. It is still purring away in the background as I write this article. I really enjoyed the build and it is a fantastic cheap entry into Stirling Engine model engineering. For a blow by blow photo log of the build check out the build article. The operating tolerances of the engine are forgiving and allowed me to quickly get it up and running then fiddle until it ran at approximately 500 rpm. The kit is suitable to anyone who knows the right end of a screwdriver and has an ounce of patience. Some care is required as the kit is made of light weight stamp cut cardboard with some metal components. Once it is completed it appears robust and should have a long life time with some care in handling and storage between operations.…

Read more: The Ecorun 2.0 Stirling Engine Kit Product Review