An investigation of a novel cooling system for chilled food display cabinets

The modern retail cabinets that are used for chilling and displaying food in shops are described in this paper. The deficiencies of the purely convective heat transfer mechanism used to cool food in modern cabinets are highlighted. A novel heat transfer system that provides an integrated conductive/convective cooling mechanism is then proposed. A purpose-developed finite difference model and its application in the study of the novel cooling system are presented in this paper. The model was used to evaluate the performance of the mechanism compared with the conventional convective system. The results indicate that the proposed novel system can provide improved heat transfer, which contributes to lower core food temperatures of approximately 2.5−3.5 K. This can lead to significant reductions in energy and capital costs as well as improvements in food quality and shelf-life. Furthermore, the use of this cooling system could avoid the requirement for electric defrost, which is energy-intensive.

Download Full-text

Thermoelectric Cooling Analysis Using Modified-Graphical-Method for Multidimensional-Heat-Transfer-System

Journal of Electronic Packaging ◽

10.1115/1.4004847 ◽

2011 ◽

Vol 133 (3) ◽

Cited By ~ 1

Author(s):

Huy N. Phan ◽

Dereje Agonafer

Keyword(s):

Heat Transfer ◽

Graphical Method ◽

Cooling System ◽

Coefficient Of Performance ◽

Optimum Operating ◽

Transfer System ◽

Thermoelectric Coolers ◽

Thermoelectric Modules ◽

Active Cooling ◽

Heat Transfer System

Comprehensive analysis of microelectronic cooling systems utilizing thermoelectric modules is time consuming because it involves solving many parametric equations, which require solving complex mathematical equations or the assistance of an expensive computation-fluid-dynamic software. In this study, a modified-graphical method (MGM) based on a previous study by Lineykin and Ben-Yaakov is proposed to analyze an active cooling system using thermoelectric modules. The MGM provides quicker visualization of the cooling requirement such as the optimum operating currents, temperature of the hot side, and coefficient of performance without the need of using any manufacturer’s proprietary data. In addition, the MGM is designed to analyze a multidimensional-heat-transfer-system utilizing thermoelectric modules (Phan, H., and Agonafer, D., 2010, “Experimental Analysis Model of an Active Cooling Method for 3D-ICs Utilizing Multidimensional Configured Thermoelectric Coolers,” ASME J. Electron. Packag. 132(2), p. 024501).

Download Full-text

Elastocaloric Cooling: System Design, Simulation, and Realization

Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies ◽

10.1115/smasis2018-7982 ◽

2018 ◽

Author(s):

Felix Welsch ◽

Susanne-Marie Kirsch ◽

Nicolas Michaelis ◽

Paul Motzki ◽

Marvin Schmidt ◽

...

Keyword(s):

Heat Transfer ◽

Heat Source ◽

System Design ◽

Cooling System ◽

Coefficient Of Performance ◽

Transfer System ◽

Vapor Compression ◽

Cooling Systems ◽

Elastocaloric Cooling ◽

Heat Transfer System

Elastocaloric cooling is a novel environment-friendly alternative to vapor compression-based cooling systems. This solid-state cooling technology uses NiTi shape memory alloys (SMAs) as cooling medium. SMAs are well known for lightweight actuator systems and biomedical applications, but in addition, these alloys exhibit excellent cooling properties. Due to the high latent heats activated by mechanical loading/unloading, large temperature changes can be generated in the material. Accompanied by a small required work input, this also leads to a high coefficient of performance superior to vapor compression-based systems. In order to access the potential of these alloys, the development of suitable thermodynamic cooling cycles and an efficient system design are required. This paper presents a model-based design process of an elastocaloric air-cooling device. The device is divided into two parts, a mechanical system for continuously loading and unloading of multiple SMA wire bundles by a rotary motor and a heat transfer system. The heat transfer system enables an efficient heat exchange between the heat source and the SMA wires as well as between the SMA wires and the environment. The device operates without any additional heat transfer medium and cools the heat source directly, which is an advantage in comparison to conventional cooling systems. The design of this complex device in an efficient manner requires a model approach, capable of predicting the system parameters cooling power, mechanical work and coefficient of performance under various operating conditions. The developed model consists of a computationally efficient, thermo-mechanically coupled and energy based SMA model, a model of the system kinematics and a heat transfer model. With this approach, the complete cooling system can be simulated, and the required number of SMA wires as well as the mechanical power can be predicted in order to meet the system requirements. Based on the simulation results a first prototype of the elastocaloric cooling system is realized.

Download Full-text