Document Type : Review Article
Faculty of Mechanical Engineering, Semnan University, Semnan, Iran
Refrigerators and freezers are commonly used for food preservations. Also refrigerated truck trailers and open-type refrigerator display cabinets appliances used for keeping the food in special conditions. These appliances need to be low energy consumer with having good temperature conditions for keeping the food compartments in a desired temperature range. One solution to this end is using cold storage materials called phase change materials (PCMs). PCMs have high latent heat of fusion and phase change in a narrow temperature range which makes them possible solution in energy saving field. This paper reviews cold storage techniques in food preservation appliances such as refrigerators, freezers, refrigerated truck trailers, open-type refrigerated display cabinets. Different thermal storage techniques beside different materials used in this field are briefly introduced. The main drawback of PCMs are their low thermal conductivity which is enhanced using enhancement techniques such as fins and extended surfaces, PCM embedded metal foams, using nanoparticles and Multiple PCM method techniques are discussed. Finally, researches in the field of employing cold storage materials in food preservation devices are reported and tabulated.