Numerical investigation of thermoacoustic refrigerator at weak and large amplitudes considering cooling effect

In this paper, OpenFOAM package is used for the first time to simulate the thermoacoustic refrigerator. For simulating oscillating inlet pressure, we implemented cosine boundary condition into the OpenFOAM. The governing equations are the unsteady compressible Navier-Stokes equations and the equation of state. The computational domain consists of one plate of the stack, heat exchangers, and resonator. The main result of this paper includes the analysis of the position of the cold heat exchanger versus the displacement of the pressure node at large amplitude for successful operation of the refrigerator. In addition, the effect of the input power on the successful operation of the apparatus has been investigated. It is observed that for higher temperature difference between heat exchangers, the time of steady state solution is longer. We show that to analyze and optimize the thermoacoustic devices, both heat exchangers should be considered, coefficient of performance (COP) should be checked, and the successful operation of the refrigerator should be evaluated.