Influence of Heat Exchanger Design on the Thermal Performance of a Domestic Wine Cooler Driven by a Magnetic Refrigeration System

Abstract

Conventional and not-in-kind refrigerators require heat exchangers for their operation. Yet, most magnetic cooling studies do not take full account of those components despite their importance in defining the cooling capacity and temperature span. To investigate the influence of heat exchanger design parameters on the performance of magnetic refrigerators, a model was developed to integrate the heat exchangers, regenerators and thermal reservoirs. The results were compared with data generated in an apparatus that emulates the conditions of the thermal fluid supplied by the regenerators to a cold heat exchanger positioned inside the cabinet of a retrofitted 130-liter wine cooler. Six tube-fin heat exchangers were evaluated to identify the most suitable geometry (number of tube rows and fin density) for the compact magnetic refrigerator. Numerical simulations described the influence of the heat exchanger on the regenerator performance in terms of the liquid stream effectiveness. For a temperature span of 20 • C between the external environment and the refrigerated compartment, the best heat exchanger/fan assembly resulted in a cooling capacity reduction of 37% and a temperature span increase of 32%, in comparison with an idealized system. The expected system coefficient of performance (COP) and second-law efficiency were 1.8% and 13%, respectively.

Model-based trade-off curves to support the set-based concurrent engineering of highly innovative projects

“…We observed how the ToC contributed to the NDP and collected data through interviews, workshops, documents, and observation. The ToC applied in the project originated in the models for the Active Magnetic Regenerators (AMR) (Vieira et al, 2021), Magnetic Circuits (MC) (Trevizoli et al, 2015), Heat Exchangers (HEx) (Peixer et al, 2022), and Hydraulic System (HS) and were validated with data incoming from experimental means. The development team performed weekly integration events to build agreements on the DS.…”

“…We generated model-based ToC to enable the NDP and DS screening. The AMR (Vieira et al, 2021; Peixer et al, 2022) were modelled through energy and momentum conservation equation. The MC was modelled by Maxwell Equations (Fortkamp et al, 2023; Trevizoli et al, 2015), while the HS modelling consisted of hydraulic theory.…”