Stability Analysis of Thermoacoustic Engines

The stability analysis of a thermoacoustic engine has been performed to predict the appearance of acoustic oscillations. The analysis was applied on both a negligible length stack as well as a considerable length stack, including viscosity effects. The predictions of the critical gradient were in agreement with previous results obtained in other studies. The approach presented in this paper offers conceptual advantages and improves the understanding of thermoacoustic engine behaviour. The present methodology is also useful for the analysis of dissipative structures such as acoustic waves emerging from an unstable thermodynamic state.