Simulation of a traveling-wave thermoacoustic engine using computational fluid dynamics

Abstract

A two-dimensional computational fluid dynamics (CFD) simulation study of a traveling-wave thermoacoustic engine is presented. The computations show an increase of the dynamic pressure when a linear temperature difference is applied across the regenerator. An amplification of the acoustic power through the engine is also illustrated. A satisfactory agreement between the calculated and expected gains of the traveling-wave thermoacoustic engine is obtained. The expected gain is defined as the ratio of the absolute temperatures at the ends of the regenerator. Nonlinear phenomena that cannot be captured by existing linear theory, like streaming mass flows and vortices formation, are also visualized. It is concluded that CFD codes could be used in the future to predict and optimize thermoacoustic systems. This is an important step towards the development of nonlinear simulation tools for the high-amplitude thermoacoustic systems that are needed for practical use.