THE EFFECT OF GRAVITY ON HEAT TRANSFER BY RAYLEIGH STREAMING IN PULSE TUBES AND THERMAL BUFFER TUBES

摘要

Thermoacoustic engines and refrigerators use the interaction between heat and sound to produce acoustic energy or to transport thermal energy. Heat leaks in thermal buffer tubes and pulse tubes, components in thermoacoustic devices that separate heat exchangers at different temperatures, reduce the efficiency of these systems. At high acoustic amplitudes, Rayleigh mass streaming can become the dominant means for undesirable heat leak. Gravity affects the streaming flow patterns and influences streaming-induced heat convection. A simplified analytical model is constructed that shows gravity can reduce the streaming heat leak dramatically.