Thermoacoustic heat transportation and energy transformation Part 3: Adiabatic wall thermoacoustic effects

Abstract This paper discusses the acoustic wave motion and thermoacoustic effects in a sound channel with adiabatic walls. In this case, the main parameters governing the propagation of sound waves are the relative width and the temperature gradient. The key thermoacoustic effect is the mutual transformation of the acoustic energy and the heat energy. The main parameter governing the energy transformation is the temperature gradient. A power production critical temperature gradient exists; when the local temperature gradient is greater than the critical value, the acoustic work increases (by decreasing the heat flux), otherwise it decreases. A heat pump critical temperature gradient also exists; when the local temperature gradient is smaller than the critical value, heat is pumped from the cold to the hot end (by decreasing the acoustic work flux), otherwise heat flows from the hot to the cold end.