Investigation of Effective Parameters on a Thermal Load in a Thermo-Acoustic Refrigerator

Mohammadi, A.; Alavi, S. M. A.

doi:10.22060/mej.2016.782

Investigation of Effective Parameters on a Thermal Load in a Thermo-Acoustic Refrigerator

Document Type : Research Article

Authors

Mechanical Engineering Department, Mashhad Branch, Islamic Azad University, Mashhad, Iran

10.22060/mej.2016.782

Abstract

This article aims to investigate the effects of various parameters on the thermal load. The governing equations include continuity and Navier-Stokes equations for the flow field and the energy equation for the temperature distribution in transient mode. Numerical simulation of the thermoacoustic refrigerator by taking the non-zero thickness of the plate stack into account, that is a conjugate heat transfer problem, in a form of 2D has been performed in FLUENT software. Real simulation of thermoacoustic refrigerators needs a consideration of both heat exchangers, whereas in most simulations one or both heat exchangers have been neglected. Results are influenced by the steady state. Input dynamic pressure should be adjusted according to the temperature of the heat exchanger. The results demonstrate the effect of the distance of the plates on the average thermal load suggesting that the distance between the plates should be four times of the thickness of the plates so that the device works properly. By increasing the distance of the plates thermal load decreases. This is mainly because of pressure amplitude reduction induced by an increase in the distance between the plates.

Highlights

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