An Analytical Application: Optimization of a Stirling Engine Based on the Schmidt Analysis and on the Adiabatic Analysis
Stirling engines are external combustion engines converting thermal energy into mechanical energy by alternately compressing and expanding a fixed quantity of air or other gas (called the working or operating fluid) at different temperatures. Stirling engines were invented by Robert and James Stirling in 1818. Despite their high efficiency and quiet operation they have not imposed themselves over the Diesel and Otto engines. In recent years interest in Stirling engines has grown, since they are good candidates to become the core component of micro Combined Heat and Power (CHP) units. In this chapter, we discuss an optimization experiment performed on Stirling engines. In particular, optimization algorithms are applied to the Schmidt and to the adiabatic analyses. These are two simple and rather idealized analytical models of the Stirling machine. Before discussing the optimization issue we briefly recall the basic elements of the Stirling cycle, and the Schmidt and the adiabatic analyses.