Refrigerated display cabinets as a type of cooling system is preferable commonly in food shops and grocery store to prevent foods from warm air. They do not have much more efficient compared to the cabinets with glass doors because of the interactions between air curtain. This paper presents experimental and numerical methods to seek energy performance of the horizontal refrigerated display cabinets in terms of design parameters. Two geometry with/without airfoil were designed and evaluated the effects of discharge velocity to create more efficient air curtain. 2D Computational Fluid Dynamics (CFD) model was performed to assess the effect of discharge flow on the cooling load performance of the horizontal display cabinet. The results showed that the airfoil design has increased the efficiency of the air curtain with achieving a more effective air curtain, resulted in mitigation of the ambient warm air infiltration into the cabinet. The return air temperature of the cabinet with airfoil decreased from 272.45 K to 270.62 K compared to the one without airfoil due to more effective air curtain. In this way, the cooling capacity of the refrigeration system has been decreased by 3.82% with airfoil usage. It is also concluded that the air temperature inside the cabinet and the cooling capacity have been decreased by 3.5°C and 2.82%, respectively when Case 7 for used the new type airfoil and Case 1 with the same air velocity are compared.

With the rapid increase in population in the world, people's demands for chilled and frozen foods are also increasing. The healthy and energy efficient cold storage of foods has become an important issue. In this context, studies on the efficiency and performance of energy management models including automatic control techniques on cooling systems have been investigated in recent years. The purpose of this study is to give information about faults, traceable energy management models and control systems in the perspective of cooling systems. Maintenance of cooling systems, malfunctions and their late detection cause time and cost problems. The decrease in the performance of the cooling system or the occurrence of malfunctions cause economic costs as well as energy consumption. Controlling the changes in pressure, temperature and electricity consumption values ​​in cooling systems and comparing them with standard operating conditions is one of the methods used for fault detection. Faults that may occur in cooling systems; compressor, condenser, evaporator, expansion element and fan failures, thermal failures, phase protection relay failures, under/over refrigerant charge, probe failures, night curtain electric motor failure, condenser-evaporator surface pollution. Errors and malfunctions occurring in the cycle cause the parameters under normal operating conditions and accordingly the cooling performance coefficient to change. Traceable energy management models are needed to detect faults and prevent them in a short time. With the design and implementation of these models, long-term damage to the system is prevented by reducing energy, maintenance and repair costs. In the design of traceable energy management models and control systems for cooling systems; set point and management, alarm notification and management, designing algorithms with precise temperature control will provide energy efficiency.

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Süpermarketlerde teşhir tipi plug-in soğutucular yaygın olarak kullanılmaktadır. Bu soğutucularda şebekeye bağlı drenaj sistemi bulunmadığından, biriken defrost suyu PTC rezistans yardımı ile uzaklaştırılmaktadır. PTC rezistansının enerji tüketimi toplam enerji tüketiminin yaklaşık %20’sini oluşturmaktadır. Nihai enerji tüketiminin birincil enerji kaynaklarından karşılandığı düşünüldüğünde; fosil yakıtların azalması ve enerji maliyetlerinin artması ile tüketilen enerjinin daha verimli kullanılması gerekmektedir. Bu çalışmada, kompresör çıkışında kızgın buhar halindeki soğutucu akışkan kompresör basma hattı boruları ile defrost kabında bulunan durgun su içerisinden geçirilmiştir. Defrost kabı içerisinde bulunan basma borularına ilave kanatçıklar eklenerek ısı transferi artırılmış ve enerji tüketimi azaltılmıştır. Bu sayede soğutucunun enerji tüketimi azaltılarak mevcut sistemde “E” olan enerji sınıfı yeni tasarım ile “D” sınıfına yükseltilmiştir. Böylece çevre dostu bir tasarım ortaya koyulmuş ve birincil enerji tüketimi düşürülerek 1 adet soğutucu için 11,138 kg/gün CO2 emisyonu azaltılmıştır.

With the increase in electricity consumption and price, energy efficiency in industrial refrigeration systems becomes an even more important issue. The performance of the industrial refrigeration system can be reported by creating energy labeling according to the energy efficiency index value. In this study, the industrial refrigeration system was evaluated in terms of energy performance with proposed a fan control technique and performed an environmentally friendly design using propane (R290) refrigerant. In addition, a new control process was developed for the management of evaporator and condenser fans, and the effect of this process on the cooled package temperatures and energy consumption was investigated. With this new technique, a 25.2% improvement was achieved in the total energy consumption of the industrial refrigeration system. It was observed that the cooled package temperatures were between −1 and +5°C throughout the experiment. The EEI value of the industrial refrigeration system has increased from class “E” to class “D” using a new control technique.