2D MODEL NUMERIC AMR, MODELLING AND SIMULATION OF MAGNETOCALORIC EFFECT

In this article, the study of gadolinium material is focused on determining the constants and properties of the material, the analysis of substructures and the orientation of dipole moments. Research into material aspects provides important information on atomic-level sub-phenomena in the field of the main magnetocaloric phenomena for the magnetic refrigeration regenerator (AMR). The experimental study is mainly based on testing the magneto-caloric material with different magnetization equipment, developed to measure more precise and fine details, magnetic refrigerator, AMR prototype development and the like. The method used uses differential equations. For both cases, where the loads are relatively simple and for more complex cases, the method can be easily applied.

Use of Magnetocaloric Material for Magnetic Refrigeration System: A Review

Our daily need to cooling system is grown up. The used cooling systems are the source of the harmful changes in the global climate. And so, we need to search a new alternate cooling systems applying environmentally friendly technology that may help in decreasing the pollutions in our world. The progress in materials science allows to use some materials for cooling purposes. This new class of materials is so called "magnetic refrigerator". The basics of magnetic refrigeration depends on the magneto-caloric properties to reach low temperatures and obtain cooling system. The advantage of magnetic refrigerator (MR); First, the cooling efficiency is higher than conventional vapor refrigerator CVM where its cooling efficiency ~30-60% while the cooling efficiency in CVM ~ 5-10%. Second, MR can be more compactly built. Third, it is safe and an environmentally friendly cooling. In this work, we will highlight on the scientific efforts to find optimum properties to be applied as the magnetic refrigeration. In this review the highlights of the scientific efforts to seek for the best alternative materials to be used as a magnetic refrigeration applications. The low coast and small size of magnetic cooling is one the important advantage. This review consists of five sections; I. Introduction, II.Synthesis of MC materials, III. Crystal structure of MC materials and IV. Characterization and applications of MC materials, and V. Conclusions.

Looking for Energy Losses of a Rotary Permanent Magnet Magnetic Refrigerator to Optimize Its Performances

In this paper, an extensive study on the energy losses of a magnetic refrigerator prototype developed at University of Salerno, named ‘8MAG’, is carried out with the aim to improve the performance of such a system. The design details of ‘8MAG’ evidences both mechanical and thermal losses, which are mainly attributed to the eddy currents generation into the support of the regenerators (magnetocaloric wheel) and the parasitic heat load of the rotary valve. The latter component is fundamental since it imparts the direction of the heat transfer fluid distribution through the regenerators and it serves as a drive shaft for the magnetic assembly. The energy losses concerning eddy currents and parasitic heat load are evaluated by two uncoupled models, which are validated by experimental data obtained with different operating conditions. Then, the achievable coefficient of performance (COP) improvements of ‘8MAG’ are estimated, showing that reducing eddy currents generation (by changing the material of the magnetocaloric wheel) and the parasitic heat load (enhancing the insulation of the rotary valve) can lead to increase the COP from 2.5 to 2.8 (+12.0%) and 3.0 (+20%), respectively, and to 3.3 (+32%), combining both improvements, with an hot source temperature of 22 °C and 2 K of temperature span.