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由于具有较高的储热能力和传热速率,堆积床相变储热被认为是一种很有潜力的储热方法.在堆积床中,壁面效应会影响相变胶囊的填充结构,从而引起径向孔隙率的振荡.本研究建立了一个基于球体实际堆积过程的三维堆积床相变储热模型,以描述径向孔隙率的振荡分布,并分析了其内部的流动和传热情况.通过在堆积床中沿径向不同位置截取圆柱面,揭示了相变胶囊的排列与径向孔隙率之间的对应关系.径向孔隙率的振荡分布导致换热流体速度呈不均匀分布,因此相变材料的径向温度分布和液相分数分布受到影响.此外,本文讨论了不同的无量纲参数(如管与胶囊的直径比、雷诺数和史蒂芬数)对换热流体和相变材料径向特性的影响.结果表明,不同的直径比对应于不同的径向孔隙率分布.此外,随着直径比的增加,在壁面附近区域换热流体速度显著变化,而中心区域换热流体速度的不均匀性将减小.雷诺数和史蒂芬数对换热流体的相对速度分布有轻微影响,而更高的雷诺数可导致速度成比例地提高,史蒂芬数的增加可加快堆积床相变储热系统的储热过程.“,”Owing to its high heat storage capacity and fast heat transfer rate, packed bed latent heat storage (LHS) is considered as a promising method to store thermal energy. In a packed bed, the wall effect can impact the packing arrangement of phase change material (PCM) capsules, inducing radial porosity oscillation. In this study, an actual-arrangement-based three-dimensional packed bed LHS model was built to consider the radial porosity oscillation. Its fluid flow and heat transfer were analyzed. With different cylindrical sub-surfaces intercepted along the radial direction in the packed bed, the corresponding relationships between the arrangement of capsules and porosity oscillation were identified. The oscillating distribution of radial porosity led to a non-uniform distribution of heat transfer fluid (HTF) velocity. As a result, radial temperature distributions and liquid fraction distributions of PCMs were further affected. The effects of different dimensionless parameters (e.g., tube-to-capsule diameter ratio, Reynolds number, and Stefan number) on the radial characteristics of HTF and PCMs were discussed. The results showed that different diameter ratios correspond to different radial porosity distributions. Further, with an increase in diameter ratio, HTF velocity varies significantly in the near wall region while the non-uniformity of HTF velocity in the center region will decrease. The Reynolds and Stefan numbers slightly impact the relative velocity distribution of the HTF—while higher Reynolds numbers can lead to a proportional improvement of velocity, an increase in Stefan number can promote heat storage of the packed bed LHS system.