The Stirling Engine uses cyclic compression and expansion of air at different temperatures to convert heat energy into mechanical work. It is designed such that the two pistons operate a quarter cycle out of phase with each other so that when the heated piston is all the way out, the cooled piston is moving in, and the same heated/cooled air is shared between the two pistons. When the air behind the heated piston is heated, the heat causes an expansion in outward pressure, which forces the piston outward. When it is all the way out, the cool air-side piston is pushing back in, which forces cooled air behind the heated piston, decreasing the temperature of that air and therefore decreasing the pressure behind that piston. That piston falls back inward, pushing heated air behind the cooled piston, pushing that piston outward. Rinse, repeat.
Be careful with the fire. A certain mishap involving this device, various flammable liquids, and a paper towel led to a certain staff member's smart-ass sister making one of these for him:
The Stirling Engine uses cyclic compression and expansion of air at different temperatures to convert heat energy into mechanical work. It is designed such that the two pistons operate a quarter cycle out of phase with each other so that when the heated piston is all the way out, the cooled piston is moving in, and the same heated/cooled air is shared between the two pistons. When the air behind the heated piston is heated, the heat causes an expansion in outward pressure, which forces the piston outward. When it is all the way out, the cool air-side piston is pushing back in, which forces cooled air behind the heated piston, decreasing the temperature of that air and therefore decreasing the pressure behind that piston. That piston falls back inward, pushing heated air behind the cooled piston, pushing that piston outward. Rinse, repeat.
Be careful with the fire. A certain mishap involving this device, various flammable liquids, and a paper towel led to a certain staff member's smart-ass sister making one of these for him: