The following machines were made under freshman's technical practice of our laboratory. The freshman did design machines and made them by themselves 1996-1997. Directed by Dr. Shinozuka, Jun.

"Stirling Engine" is developed by Robert Stirling. Stirling Engine theoretically has the same cycle as the "Carnot's cycle". Striling Engine is very clean and economical engine. This engine is very curious mechanism, because this engine needs only the temperature variation. When the air temperature is forced to raise, the air pressure shall be raised. While the air is cooled, the air pressure shall be decompressed. In order to separate these high temperature portion and low temperature portion, this engine has the displacer. The optimum size of displacer diameter is 98% of its cylinder diameter. In short, there is a optimum clearance between the displacer and its cylinder.

The following four figures show the mechanism schematically.

This is our Stirling Engine Model. This machine works well under the condition that the temperature difference is around over 500 centigrade. The heat source is electric heater.

When the heater temperature is about 600 centigrade, the fly wheel rotates about 1000 rpm. In this case, the temperature of cooling portion is about 100 centigrade.

Left hand photograph shows the general view of this engine. The right hand side port to the fly wheel is the power piston. The left is the heating portion and cooling portion which has the displacer in it. Right hand photograph shows the system of this equipment. White block is the electric heater. Using this electric heater the temperature can be raised upto 800 centigrade.

Fun, fun, fun..... As increases heater temperature, as increases the revolution of fly wheel. But, the displacer is made by aluminum, so ....... If we could use the hydrogen gas instead of the air, the power would be much more higher.

"Steam Engine" is one of the very popular engine.

This is our model engine. Power source is not the vapor but the compressed air distributed by the air compressor.
Powerful!