Coupling Between Electrodynamic Loudspeakers and Thermoacoustic Cavities

In thermoacoustic engines, the strong coupling between the sound source and its front and rear loads yields the necessary acoustic energy to be used by fluid particles in the vicinity of the stack for heat transfer from cold to hot thermal sources. An analytical study of this coupling is presented when using available loudspeakers, in order to match together the components of the whole system (acoustic source, thermoacoustic cavity and rear cavity). Current models for loudspeakers and thermoacoustic refrigerators are used to provide electrical networks which describe the behaviour of the coupled system. Theoretical and experimental results concerning the frequency response of the system, the acoustic power flux in the cavity and the efficiency of the coupled system are presented.