The study numerically investigates the melting of phase change material in a two-dimensional rectangular region with an aspect ratio of 10/7 under sidewall heating conditions, utilizing the enthalpy method. It comprehensively examines the effects of varying Rayleigh numbers (), Prandtl numbers (), and Stefan numbers (), corresponding to different material properties and operating conditions. The results regarding the melting rate and pattern, characteristic melting time and heat transfer properties reveal that both and exert more pronounced effects on the phase change process compared to , with demonstrating significance only for . It is important to note that convective effects ultimately manifest unless is sufficiently small to yield nearly stationary flow, leading to deviations in the mean interface evolution from one-dimensional conduction-only results. Additionally, it can be shown that the non-dimensionalized stored energy is approximately proportional to the mean interface position as , which is consistent with the simulation results. Although, the maximum stored energy is solely dependent on , the average energy storage rate increases with and decreases with . Our investigations provide valuable insights into the selection of phase change materials and operating conditions for energy storage systems that involve solid-liquid phase change.

中文翻译：

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不同控制参数下侧壁加热熔化过程的数值研究

该研究利用热函法对侧壁加热条件下相变材料在纵横比为 10/7 的二维矩形区域内的熔化进行了数值研究。它全面检查了不同的瑞利数 ()、普朗特数 () 和斯特凡数 () 对应于不同的材料特性和操作条件的影响。关于熔化速率和模式、特征熔化时间和传热特性的结果表明，与 相比， 和 对相变过程产生更显着的影响，仅对 表现出显着性。值得注意的是，对流效应最终会显现出来，除非足够小以产生几乎静止的流动，从而导致平均界面演化与仅一维传导结果的偏差。此外，可以看出，无量纲存储能量与平均界面位置近似成正比，这与模拟结果一致。虽然最大存储能量仅取决于，但平均能量存储率随 增加并随 减少。我们的研究为涉及固液相变的储能系统的相变材料的选择和操作条件提供了宝贵的见解。