Stirling Engine and Candle

Steam Engine

Compression and Expansion of an Ideal Gas

CD Demos :

Stirling Engine

Relevant Resource questions :

Other Relevant WEB sites :

Koichi Hirata from Japan builds his own Stirling Engines.
His web page also gives some excellent descriptions and instructions for how to make your own Stirling Engines. Highly recommended!

Brent H. Van Arsdell from the American Stirling Company builds a model Stirling engine called the MM-1 which runs on ice.

Concepts demonstrated :

• thermal expansion
• conversion of heat to work
• efficiency
• PV cycle

Equipment needed :

• Stirling engine
• bunsen burner
• matches

• The engine is mounted on top of a large retort stand as shown.
• A bunsen burner provides the heat source.

This engine contains a gas in a closed system. ie fuel does not enter and exhaust does not leave. The hot energy source is external to the cylinders. Some of the energy transferred as heat flow from the hot source (burner or candle) is converted to mechanical energy as output of the engine. The mechanism for the conversion to occur is as follows

Thermal expansion of air in chamber causes the overall pressure to increase thereby moving piston B up. In doing so A moves down, hot air goes into the cold chamber and decreases in volume (due to cooling). B then moves down to repeat the cycle.

How to use the Demonstration :

• Use the First Law of Thermodynamics. Look at convection, mechanical and thermal domains (- conversion ?), often showing students P,V diagrams. Link the demonstration to the P,V,T apparatus, then show them the engine. This puts the theory and the experimental apparatus into perspective. The engine comprises gas in a cylinder which is being compressed/expanded.
• If possible, link the demonstration to a computer animation.

  (The animation is yet to be done.)

  Otherwise, include P,V,T transducers and plot the relevant thermal graphs on a computer.

  (This is also yet to be done.)

Things to do or add :

• Computer animation in parallel showing the process (moving slowly) would be good.
• Incorporate P, V, T transducers in the apparatus and send the output from these transducers to a computer to obtain PV, etc diagrams.
• The poster needs to be redone and then could be used on Open Days, etc.

• This experiment was developed as part of the Talented Student's Programme in Physics at the University of Sydney.