الفهرس 
Introduction of Phase Change Material Thermal Storage TankOnly 14 pages are availabe for public view
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Abstract
As a general rule, the world’s energy consumption is rapidly rising, and conventional fuel reserves are decreasing globally. Therefore, the scientific community agrees that renewable energy is one of the best options for supplying energy to many regions of the world. Solar, wind, bio, geothermal, tidal, and hydropower are examples of renewable energy sources and the same time clean energy and friendly to environment. However, almost all of these energy sources are constrained by their high prices. Additionally, the intermittent nature of solar, wind, and tidal energy is what separates them from other forms of energy because they are not always available. Hence, energy storage can be used to solve this intermittent issue. In fact. the most promising energy storage technologies use phase change materials, which offer a high energy storage density at a constant temperature, ; nevertheless, a significant drawback is the materials’ poor heat conductivity. The present study aims to model the melting process and examine the ideal design parameters for horzontial phase-change energy storage tanks with a steady and rapid melting rate. A 2-D axisymmetric mathematical model has been developed using ANSYS 17.2. Moreover, published experimental data have been used to validate the model. In addition, the main factors taken into account include investigating the new elliptical inner tube design with aspect ratio (1, 0.9, 0.8, 0.7, and 0.5), the eccentricity ratios (0, 0.1, 0.2, 0.3, 0.4, and 0.5), the inclination (0 o, 30 o, 60 o, and 90 o) of the inner tube, and the multiplication of inner elliptical tubes (two, three, and four ellipses) with different arrangements. The results of the present study have revealed that the eccentricity ratio of 0.5 has the fastest melting rate for all aspect ratios. However, aspect ratio 1 has the quickest melting rate at an eccentricity ratio of 0.5. For an aspect ratio of 0.5, the inner elliptical tube’s highest and lowest average melting rates are 0.00516 and 0.00417 kg/min for the vertical inner elliptical tube (θ =90o) and horizontal inner elliptic (θ =0o), respectively. In fact, the multiplication of inner elliptical tubes has affected the melting characteristics. For a two-ellipse configuration, design 2 (vertical ellipses with vertical arrangement) has increased the melting rate by 81.6% over original design (one vertical ellipse concentric with outer tube at aspect ratio 0.5). For three-ellipse inner arrangements, when compared to original design, the melting rate of design 6 (vertical ellipses with triangle arrangement) has improved the melting rate by 141.7%. For four-ellipse internal tubes, designs 6 (vertical ellipses with square arrangement) has a melting rate that is greater than the original design by 112.5%.