In this study, for a near-room-temperature magnetic cooling system, a decoupled multiphysics numerical approach (Magnetism, Fluid Flow, and Heat Transfer) is developed using a commercial CFD solver, ANSYS-FLUENT, as a design tool. User defined functions are incorporated into the software in order to take into account the magnetocaloric effect. Magnetic flux density is assumed to be linear during the magnetization and demagnetization processes. Furthermore, the minimum and maximum magnetic flux densities (Bmin and Bmax) are defined as 0.27 and 0.98, respectively. Two different sets of analyses are conducted by assuming an insulated cold heat exchanger (CHEX) and by defining an artificial cooling load in the CHEX. As a validation case, experimental work from the literature is reproduced numerically, and the results show that the current methodology is fairly accurate. Moreover, parametric analyses are conducted to investigate the effect of the velocity of heat transfer fluid (HTF) and types of HTF on the performance of the magnetic cooling system. Also, the performance metrics of the magnetic cooling system are investigated with regards to the temperature span of the magnetic cooling unit, and the cooling load. It is concluded that reducing the cycle duration ensures reaching lower temperature values. Similarly, reducing the velocity of the HTF allows reducing the outlet temperature of the HTF. In the current system, the highest temperature spans are obtained numerically as around 6 K, 5.2 K and 4.1 K for the cycle durations of 4.

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In this study, the influences of inlet temperature and velocity of the heat transfer fluid and the capsule material on the performance of a latent heat thermal energy storage unit is numerically investigated. The enhanced thermal conductivity approach is implemented into the ANSYS‐FLUENT software to consider the natural‐convection‐dominated melting process within the capsules. The accuracy of the procedure is checked by comparing the current findings for inward melting against the numerical results from the literature. The comparative results reveal that the proposed approach is successfully incorporated, and the maximum deviation is obtained to be less than 10%. Results of the parametric analyses are represented regarding the first and second laws of the thermodynamics. The time‐wise variations of the melting front, the mean temperature of the phase change material, and the rate of entropy generation are evaluated. Increasing the inlet temperature and velocity of air significantly reduces the time for complete melting. The total time for melting is reduced by half when the inlet temperature of air is increased from Tm + 10 to Tm + 20 and the entropy generation rate increases more than four times. Besides, increasing the air inlet velocity from 0.5 m/s to 3.0 m/s doubles the entropy generation.

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