الفهرس 
Introduction and Literature reviewOnly 14 pages are availabe for public view
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Abstract
Latent heat thermal energy storage (LHTES) systems play a vital role in solving the intermittent availability of the solar energy. Shell and tube heat exchangers (STHE)s are the most widely used type of heat exchangers (HE)s for the LHTES units due to its compactness and effectiveness in storing energy. Phase change materials (PCM)s are used for storing this large heat energy quantity due to the high heat storage capacity value per unit volume. This study presents a numerical simulation of the melting and solidification process of RT44HC as a PCM enclosed in circular shell with multiple tubes array containing the heat transfer source and sink and a base case of double pipe unit; with all cases being horizontally oriented. The two-dimensional transient numerical model was validated by a previous published experimental work and showed good agreement. During the study; the amount of the PCM and heat transfer surface areas for all cases were identical. Three different arrays of line, arc, and triangular arrays were studied. The influence of changing the tube orientation of each array in the shell was applied by rotating the array with step angle of 30°. It was found that the optimal orientation for the line, arc, and triangular arrays are 0° line, 90° arc, 90° triangular array, respectively over the full melting and solidification cyclic process. In this favorable cases, the 0° line array reduced the base case total full cyclic time by 44.401 %; the 90° arc array by 16.774 %. While, the 90° triangular array prolonged the base case total full cyclic time by 1.274 %. It was concluded that the optimum orientation for all investigated cases was the 0° line array over the full cycle.