Chapter 75 - Analytical model for onset temperature difference of thermoacoustic Stirling prime movers

Abstract

The onset temperature difference of thermoacoustic Stirling prime movers is a very important parameter for utilizing low quality heat energy. This chapter establishes an analytical model to calculate it and finds its dependence on the length and porosity of the regenerator, the working gas, the oscillating frequency, and the working pressure. Thermoacoustic engine is a kind of new machine that can convert heat into mechanical work in the form of an oscillating pressure. They, especially thermoacoustic Stirling prime movers with higher achievable efficiency, have received lots of attention in recent years due to their outstanding advantages of structure simplicity, heat-driven mechanism, and environment-friendliness. The onset temperature difference of a thermoacoustic Stirling prime mover deeply depends on the length and porosity of the regenerator, the working gas, the frequency and the pressure, this analytical model can provide some guidance for designing a low onset-temperature difference engine. The conclusions are based on some simplified assumptions, in which some factors that may influence the onset temperature difference are not considered in this model, a more accurate model will be developed in future.