<p>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 <InlineEquation ID="IEq1"> <EquationSource Format="TEX">$\tau$</EquationSource> <EquationSource Format="MATHML"><math> <mi>τ</mi> </math></EquationSource> </InlineEquation>. The objective of this investigation is to optimize the <InlineEquation ID="IEq2"> <EquationSource Format="TEX">$\tau$</EquationSource> <EquationSource Format="MATHML"><math> <mi>τ</mi> </math></EquationSource> </InlineEquation>. Our methodology is based on defining the parameter vector <InlineEquation ID="IEq3"> <EquationSource Format="TEX">$V_{\tau } \left( {\dot{m}, D_{g} , \varepsilon , L_{g} , \Delta T_{ad} , N_{S} } \right)$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mi>V</mi> <mi>τ</mi> </msub> <mfenced close=")" open="("> <mrow> <mover accent="true"> <mi>m</mi> <mo>˙</mo> </mover> <mo>,</mo> <msub> <mi>D</mi> <mi>g</mi> </msub> <mo>,</mo> <mi>ε</mi> <mo>,</mo> <msub> <mi>L</mi> <mi>g</mi> </msub> <mo>,</mo> <mi mathvariant="normal">Δ</mi> <msub> <mi>T</mi> <mrow> <mi mathvariant="italic">ad</mi> </mrow> </msub> <mo>,</mo> <msub> <mi>N</mi> <mi>S</mi> </msub> </mrow> </mfenced> </mrow> </math></EquationSource> </InlineEquation>, which includes the variables influencing <InlineEquation ID="IEq4"> <EquationSource Format="TEX">$\tau$</EquationSource> <EquationSource Format="MATHML"><math> <mi>τ</mi> </math></EquationSource> </InlineEquation>. 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.</p>

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

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发表日期：

2025年7月21日

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Zoubir Guaddouche,
Ali Boumedien,
Ammar Zeghloul,
Abdelsalam Al-Sarkhi,
Ali Cherif

摘要

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 $\tau$ $τ$ . The objective of this investigation is to optimize the $\tau$ $τ$ . Our methodology is based on defining the parameter vector $V_{\tau } \left( {\dot{m}, D_{g} , \varepsilon , L_{g} , \Delta T_{ad} , N_{S} } \right)$ $V_{τ} (\dot{m}, D_{g}, ε, L_{g}, Δ T_{ad}, N_{S})$ , which includes the variables influencing $\tau$ $τ$ . 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.