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Although thermoacoustic devices comprise simple components, the design of these machines is very challenging. In order to predict the behavior and optimize the performance of a thermoacoustic refrigerator driven by a standing-wave thermoacoustic engine, considering the changes in geometrical parameters, two analogies have been presented in this paper. The first analogy is based on CFD analysis where a 2D model is implemented to investigate the influence of stack parameters on the refrigerator performance, to analyze the time variation of the temperature gradient across the stack, and to examine the refrigerator performance in terms of refrigeration temperature. The second analogy is based on the use of an optimization algorithm based on the simplified linear thermoacoustic theory applied for designing thermoacoustic refrigerators with different stack parameters and operating conditions. Simulation results show that the engine produced a high-powered acoustic wave with a pressure amplitude of 23[Formula: see text]kPa and a frequency of 584[Formula: see text]Hz and this wave applies a temperature difference across the refrigeration stack with a cooling temperature of 292.8[Formula: see text]K when the stacks are positioned next to the pressure antinode. The results from the algorithm give the ability to design any thermoacoustic refrigerator with high performance by picking the appropriate parameters.

Most numerical research on thermoacoustic devices with a stack made of parallel plates has considered a rectangular form for the plate. However, a variety of plate shapes can improve the heat transfer and performance of the stack. In this paper, a 2D numerical model based on computational fluid dynamics (CFD) analysis is used to examine the efficiency of thermoacoustic couples using a diversity of plate surfaces. For this investigation, flat plates and others profiles with corrugated surfaces (rounded and triangular surfaces) were tested to compare their performances and the effect of plate form on thermoacoustic systems. The efficiency of the thermoacoustic engine (TAE) is measured in terms of the generated acoustic pressure and the performance of the thermoacoustic refrigerator (TAR) is considered in terms of the temperature gradient along the refrigeration stack. The results showed that plates profile with irregular surfaces improves the generated acoustic pressure due to the increase of the stack porosity known as the blockage ratio (BR). The triangular shape performed better with a 10% gain than using a flat plate, followed by rounded ripples with a 5.2% increase in pressure amplitude compared to flat surfaces. Unlike in TAR, it was revealed that the stack made of flatform could produce a higher temperature difference (∆T) among the refrigeration stack extremities. By using rounded ripples, ∆T undergoes a reduction up to 52%, and 65% if using triangular ripples compared to flatform. From this investigation, it is observed that the stack with corrugated plates is the most suitable for TAE; however, the flat plates generate a higher temperature difference in TAR.

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