This video is a demonstration of a small working Stirling engine. The engine runs due to a temperature
difference applied between the top and bottom plates of the engine body. In this video the top plate is at room temperature
and the bottom plate is sitting on top of a cup filled with hot water.
Video 2: Stirling Engine & PV-diagram
The top plate of the Stirling engine was modified to accommodate simple
digital instruments from Venier to monitor the pressure and volume inside the engine.
The change in both pressure and volume of the Stirling engine are plotted in real time on the monitor in the background.
A plot of pressure versus volume (PV-diagram) is a graphical representation of the work done by the engine. The area inside
the closed path on the PV-diagram corresponds to the work per cycle done by the engine.
Video 3: PV-diagram & Friction
In the beginning of this video friction is applied to the engine by placing a sponge in contact with the flywheel and
the PV-diagram is recorded. Later, the fiction is removed and the engine starts to speed up and eventually reaches its maximum
speed. As the engine speeds up the area of the loop in the PV-diagram decreases. This is because the engine has to do more
work per cycle when the friction is applied.