Powered By Hot and Cold Water
Demonstrate the conversion of heat energy into mechanical energy with this working engine. Based upon the work of Dr. Alfred Johnson who was granted a patent on this type of heat engine in 1977, this model uses the unique property of Nitinol alloy to generate mechanical motion from heat.
Nitinol has trained into a shape at high temperature (about 600ºC) and allowed to cool to room temperature, where it can be easily deformed and welded into a loop. When heated above a transition temperature (in this application about 50ºC to 70ºC) the Nitinol object abruptly returns to its high-temperature shape with a substantial force that is able to drive the pulleys and thus create motion. This interesting demo of basic physics is simple to operate - just use hot and cold water.