Abstract This work improves a layered thermal resistance (LTR) model for the prediction of phase change times in solid-liquid phase change heat transfer. A combination of analytical and numerical approaches is applied in 1-D and 2-D solidification problems where heat conduction is dominant. In the improved layered thermal resistance (ILTR) model, the domain is discretized to layers. Based on its thermal resistance, the solidification time of each discrete layer is obtained by calculating the heat flux across the boundaries and the sensible and latent heat transfer. Unlike the quasi-steady heat conduction approach and linear temperature distribution assumption in the LTR model, the ILTR model considers transient heat conduction in each layer thus providing a better estimation of the average temperature distribution. The total solidification time is obtained by adding the solidification time of all the discrete layers. In several validations, the ILTR model shows a good agreement with the exact solution (1-D), experimental results (1-D), and numerical results (2-D). It is demonstrated that the ILTR model provides better predictions of phase change times than the LTR model, particularly under large Stefan numbers. This model could be further developed for more complicated (geometry or boundary conditions) phase change problems.

中文翻译：

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一种用于固液相变时间估计的改进分层热阻模型

摘要 这项工作改进了分层热阻 (LTR) 模型，用于预测固液相变传热中的相变时间。分析和数值方法的组合应用于热传导占主导地位的一维和二维凝固问题。在改进的分层热阻 (ILTR) 模型中，域被离散化为层。基于其热阻，通过计算跨边界的热通量以及显热和潜热传递，获得每个离散层的凝固时间。与 LTR 模型中的准稳态热传导方法和线性温度分布假设不同，ILTR 模型考虑了每一层的瞬态热传导，从而提供了对平均温度分布的更好估计。通过将所有离散层的凝固时间相加，得到总凝固时间。在多次验证中，ILTR 模型显示出与精确解 (1-D)、实验结果 (1-D) 和数值结果 (2-D) 的良好一致性。结果表明，ILTR 模型比 LTR 模型提供了更好的相变时间预测，尤其是在大 Stefan 数下。该模型可以进一步开发用于更复杂的（几何或边界条件）相变问题。特别是在很大的 Stefan 数下。该模型可以进一步开发用于更复杂的（几何或边界条件）相变问题。特别是在很大的 Stefan 数下。该模型可以进一步开发用于更复杂的（几何或边界条件）相变问题。