The Stirling cycle engine is named after the Reverend Robert Stirling who lived in Scotland between 1790 and 1878. Already in 1816 Robert Stirling obtains a patent in relating to a hot-air engine, which he and his brother James developed and construct.

What is a Stirling, or hot-air, engine?
A Stirling engine is a machine which converts thermal energy into power. They can be used as a water pump, to generate electrical energy or to drive a machine. Stirling motors are squeamish in the fuel they get. It works on every source of heat.

How does a Stirling engine work?
The principal working is based on the expansion of heated gas that will move a piston in a cylinder. The gas will be heated after a compression stroke at a low temperature. By repeating this cycle again and again a power delivering machine is constructed.

The remaining part of this page
is about the Stirling engines that I have built over the last years.

Above the model of the Ericsson hot-air engine. This machine is heated with a small gas burner. The flywheel is assembled of a hub with steel rim glued together with a thick plate of aluminium. The spokes were sawed out of the aluminium plate.

Simple hot-air engine with external water cooling system.
A Teflon bus is used to make the bushing for the displacer rod. The displacer is made of an aluminium sprayer to keep the weight as low as possible.

Hot-air engine with cylinder and verdringer under an angle of 90 degrees.

Mostly I use a double wall to lead the cooling water. The cooling water of this Stirling engine circulate in a natural way.

To keep friction as low as possible the turning part has a ball bearing.

This Stirling engine is constructed with the FIZIG drawings, which are downloadable from the internet. The scale is enlarged, based on the aluminium sprayer used as displcaer. Advantages are the low weight and less friction on the horizontal movement of the displacer in the bushing, which is made of bronze.

Picture on the left you can see the aluminum piston with the brass cylinder.

On the right shows the double wall where the cool water flows through.

Heinrici stirling engine coupled with a circulationpumps.
I used a alcohol brander for heating.

These vertical stirling engine an own design is , By this stirling engine I have used a aluminium sprayer used as displacer

The flywheel is assembled of a hub with steel rim glued together with a thick plate of aluminium. The spokes were sawed out of the aluminium plate.

Further is there a mechanical pump assembled for the necessary cool water circulation .

POPPIN. The engine works by sucking the flame from the alcohol lamp into the cylinder as the pistom travels toward bottom center. As the piston nears bdc, the valve shuts, the gasses in the cylinder cool, and atmospheric pressure pushes the piston toward the top of the cylinder. The valve opens near tdc, and the cycle repeats.