###### Abstract  
This study utilizes a simplified two-dimensional time-dependent computational fluid dynamic (CFD) model to compare the performance of single- and two-layer air curtains in an open-type multi-deck refrigerated display cabinet. Two layers of air curtain generate a more effective invisible barrier from ambient air impact that can reduce electrical energy consumption and maintain a uniform temperature distribution within the cabinet. The CFD model of a refrigerated display cabinet was validated by the experimental data. The results showed a two-layer air curtain advantage over a single air curtain. Electrical energy consumption decreased by 18.5%, and the average temperature of the test products decreased from 5.75 \({}^{\circ}\)C to 5.17 \({}^{\circ}\)C. The results obtained are important for cabinet design to improve the quality of product storage and reduce energy consumption. air curtain; air velocity; CFD simulation; heat transfer; open-type refrigerated display cabinet; temperature +
Footnote †: journal: Applied Sciences  
cases, employing the SVM algorithm leads to improved accuracy performance compared to manual parameter selection. One of the most important tasks is to investigate the impact of the environment on the cooling process. The ambient influence is a major factor that must be taken into account to achieve a well-designed air curtain. [PERSON] et al. [11] conducted a study comparing face-to-face and face-to-back placements of multi-deck display cabinets that were placed in several rows in a supermarket. The face-to-back method demonstrated advantages, including lower ambient air temperatures, stronger environmental coupling, and effective prevention of hot air. Moreover, the isotherm distributions varied, with face-to-back exhibiting higher density above and near the top, while face-to-face showed a uniform distribution above and a sparse one near the ground. This investigation holds significant importance in understanding the impact of the environment on open-type display cabinet performance. The findings highlight that the face-to-back placement method can acquire a better food refrigeration performance, and the food temperature is 0.3 to 0.5 \({}^{\circ}\)C lower than that of the face-to-face placement method [11]. [PERSON] et al. [6] investigated the impact of the customer on the cold chain. In this case, a robotic mannequin was used to systematically simulate the movement of customers inside the store and quantify the increase in air temperature and thermal load due to this disturbance. [PERSON] et al. [5] investigated the impact of ambient airflow velocity and direction on the performance of an open-type refrigerated cabinet with two air curtains and, after that, compared the performance of OTRDCs with one and two air curtains. The results show that the OTRDC with two air curtains has better performance than the OTRDC with a single air curtain, which can save energy up to 41.6%. Comparison of the electrical consumption of doored and open cases plays an essential role in energy-saving strategies. [PERSON] and [PERSON] [3] compared a typically available refrigerated display case line-up with a typical glass door refrigerated display case line-up with the aim of quantifying the difference in overall energy consumption for each type. It was established that per unit length of case line-up, the open display case line-up consumed approximately 1.3 times more energy than the doored display case line-up. For this investigation, a Coriolis mass flow meter was used to determine the refrigerant mass flow rate; electrical energy consumption was determined using kWh transducers, the ambient dry-bulk temperature was measured by thermocouples, and the relative humidity was measured with a humidity sensor. Many investigations have been carried out in terms of the jet effects of air curtains. [PERSON] and [PERSON] [2] presented the study of the entrainment of refrigerated air curtains down a wall.