الفهرس 
AbstractOnly 14 pages are availabe for public view
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Abstract
Global energy demand and consumption nowadays has reached unprecedented levels and is predicted to increase in the coming decades subsequently effectuating a growing interest in energy storage research especially the thermal energy field in hopes of breaking new ground in energy optimization. Phase change materials play a crucial role in thermal energy management by virtue of their ability to store large amounts of potential energy as a prelude to reuse when needed. Studies related to the integration of thermal systems with energy storage materials, especially widely used ones like cooling circuits, have become the focus of many researchers, with the aim of enhancing their performance regarding product preservation and energy consumption regulation. Therefore, in this study, variable PCMs with different types, patterns, and mixes were directly attached to the bottom of the frozen products stored in the refrigeration system with the aim of improving the thermal energy storage capacity over extended hours of cyclic operation, as well as working to stabilize the temperature fluctuation of frozen products through On/Off operation of the cooling system. A system enhanced by using PCMs was compared with a conventional system in order to accentuate the impact of incorporating these materials into the cooling system. A comparison between the conventional and integrated refrigeration systems was held by measuring and analyzing a number of design and operating factors affecting the two systems including the weight of the frozen products relative to the weight of the energy storage material, the ability to blast freeze, minimum product degraded temperature. Other factors are considered during planned power outages like; calculating the melting time prolongation coefficient (period factor) as well as calculating the stored energy recovery ratio using phase change materials needed for stored products preservation during power outage. This study also explores the effect of placing the frozen products of the integrated system at multiple heights, starting from direct contact with the bottom surface of the evaporator until reaching the maximum available storage shelf height inside the evaporator cabin. It is noteworthy that PCMs used in the study can be categorized as follows: Four different types of single PCMs applied separately, six cases of double PCMs formed by mixing two different types of single PCMs, and five newly developed mixtures formed by mixing multiple single PCMs in hopes of maximizing the advantages of each. The novel PCM Mixtures are developed by adding nanoparticles of aluminum oxide and copper with mixing ratios dominant by the types associated with achieving promising performance results on an individual basis. The Accuracy of the experimental results are checked by comparing a sample of the results of the current study with some previous studies using a similar type of PCM and the comparison conveyed a satisfactory convergence. In general, a new criterion is devised for choosing between different types of single PCMs according to usage. Overall, the results of the experiments have shown that some of the mixtures developed in this study are more effective in storing energy than all the other single types. The study extends to conducting an analysis of the economic feasibility of using PCMs in the home refrigerator versus the concurrent conventional one. The results indicated that implementing and operating conventional home refrigerators with new PCM mixtures is less costly than traditional refrigerators attributable to their ability to save energy.