How does a Stirling Engine Work?
A Stirling engine is a closed-cycle heat engine that turns heat into mechanical work. It is an external combustion engine where the heat comes from an external source, such as fuel burners, geothermal heat, solar heat, and fossil fuel heat. It is similar to other familiar heat engines like steam engines, diesel, and gasoline. The Stirling engine works on the principle that when air is heated it expands, and when it becomes cooled it contracts. It heats and cools air within a closed container at regular intervals, and uses the pressure changes this causes to run a piston. This cyclical operation of heat is done by having one part of the engine kept hot and another part kept cold through thermal contact with an external heat source and an external heat sink. A mechanism then shifts the air from the hot side to the cold side, back and forth. The air cannot escape because it is in a sealed chamber. When the air goes to the hot area, it swells and pushes the piston upward. When the air retu
