Sensitivity Analysis and Parametric Optimization of Flow Time in Packed-Bed Magnetic Refrigerators Using Magnetocaloric Materials: Modeling and CFD Simulation

Unlike conventional refrigeration, magnetic refrigeration deserves to be classified as a green technology. In this system, a magnetic generator (MG) replaces the evaporator of the conventional refrigeration cycle. The MG serves as the site of thermal exchange between a heat transfer fluid (HTF) and a magnetocaloric material (MCM) during a phase known as the half period, denoted as τ. The objective of this investigation is to optimize the τ. Our methodology is based on defining the parameter vector Vτm˙,Dg,ε,Lg,ΔTad,NS, which includes the variables influencing τ. A sensitivity analysis is then carried out to evaluate the individual effect of each represented parameter. The MG contains the MCM arranged as a packed bed of spheres, modeled using the Darcy–Brinkman–Forchheimer approach. This model is coupled with the conservation equations of mass and energy. The finite volume method was employed. As a result of the numerical processing, the following key outcomes were obtained: The ṁ is the most influential parameter, while the Ns has the least impact. The isotherms plots reveal the emergence of a temperature gradient directed from the hot side to the cold side, which induces a convective flow from the cold side to the hot side of the machine. These two observations highlight the effect of flow rate on the performance of the refrigeration system.