Development of a CFD model for the simulation of open horizontal refrigerated cabinet

• CFD study focused on horizontal open refrigerated cabinets. • Validated 2D model predicts air velocity and temperature fields. • Key flow instabilities linked to high energy demand identified. • Optimised 9 cm–60° visor cuts energy use by 16.15 % • CFD-based design improves product temperature uniformity. In supermarkets, food is stored in refrigerated and frozen cabinets that operate 24 h per day, 365 days per year, making them, on the one hand, huge consumers of electrical energy and, on the other, an important target for energy efficiency and decarbonisation. In recent years, new regulations on energy consumption reduction have focused on these cabinets, but efforts have focused on optimising vertical cabinets, as they are found in a higher percentage than horizontal cabinets. However, horizontal refrigerated display cabinets represent a significant proportion of the sector’s electricity demand, which makes improving their efficiency essential for reducing operating costs and greenhouse gas emissions. Unlike most previous studies focused on vertical cabinets, this study applies the validated CFD approach to horizontal open units, identifying the specific flow characteristics that most affect their thermal performance and energy consumption. In order to achieve the correct simulation of the fluid dynamics inside the cabinet and to analyse its fluid-dynamic behaviour, a correct mesh is implemented, supported by its sensitivity study, and boundary conditions are implemented. The computational model developed, validated experimentally, allows to obtain the velocity and temperature distribution of the cabinet, identifying the aspects that directly influence the energy consumption of the cabinet. It also allows to determine the speed and temperature in the discharge, due to its influence on the air curtain, and in the intake, due to its influence on the global pressure drop. Finally, with the identification of these unfavourable points, improvements are proposed that directly affect the reduction of the temperature of the packages and the energy consumption of the cabinet. These results demonstrate that the implementation of a 9 c m and 60 ° visor in the return duct improves the stability of the air curtain, reduces the energy consumption of the cabinet by 16.15 % and improves the uniformity of the stored product by 0.57 °C, demonstrating the effectiveness of CFD-based optimisation. The methodology developed can be extended to other cabinet configurations, supporting future efforts.