In the present study, the thermo-hydrodynamic performance of two different configurations of wire-mesh regenerative heat exchangers, namely in-line and staggered arrangements, was numerically investigated under turbulent oscillating flow conditions. Mathematical modeling and computational fluid dynamics simulations were carried out by considering conjugate heat transfer between the air flow and the aluminum solid matrix, temperature-dependent thermophysical properties, thermal radiation effects, and turbulence modeling. To ensure a fair comparison, both regenerators were designed with identical mass, similar porosity, and the same heat transfer surface-area-to-volume ratio, so that only the effect of wire arrangement could be evaluated.

The results showed that the regenerator geometry has a direct effect on both thermal efficiency and pressure drop. The in-line regenerator achieved an average thermal efficiency of approximately 91.6%, which represents a 3.6% improvement compared with the staggered regenerator, whose average efficiency was about 88%. Moreover, the average pressure drop in the in-line configuration was approximately 59 Pa, whereas this value reached about 95 Pa in the staggered configuration. Therefore, the use of the in-line structure reduced the average pressure drop of the system by nearly 36 Pa.