Building energy simulation (BES) tools are key instruments for sizing the PCM based system in the built environment and analyzing its effect on thermal comfort and energy demand. Due to complex solidification and melting phenomena of PCM, BES tools have limitations in predicting its performance with buildings. Computational fluid dynamics (CFD) tools are also used to model the PCM, but those models are not integrated with the building simulation models. This study aims to develop a co-simulation framework between BES tool (EnergyPlus) and CFD tool (Ansys Fluent) to model the PCM integrated built environment and compare its prediction accuracy with the most popular BES tool, i.e., EnergyPlus. Three experimental case scenarios 1) Active use of PCM, 2) Passive use of PCM during natural convection and 3) Passive use of PCM during forced convection have been modeled for prediction accuracy assessment. A common accuracy index (Root Mean Square Error) is used along with temporal temperature variation for the comparison. The results highlight that the proposed co-simulation has better prediction accuracy than the BES tool for active use of PCM and passive use of PCM under forced convection. For modeling the passive use of PCM during natural convection, BES tool is recommended. Since in the extreme climatic conditions, PCM with active use and forced convection are effective compared to the passive use of PCM, this study would be useful in modeling the built environment with PCM at early building design stages for extreme climatic conditions.

中文翻译：

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用于建筑物热管理的 PCM 耦合 EnergyPlus 和 CFD 分析


建筑能源模拟 (BES) 工具是在建筑环境中确定基于 PCM 的系统规模并分析其对热舒适度和能源需求的影响的关键工具。由于 PCM 复杂的凝固和熔化现象，BES 工具在预测其与建筑物的性能方面存在局限性。计算流体动力学 (CFD) 工具也用于对 PCM 进行建模，但这些模型未与建筑仿真模型集成。本研究旨在开发BES工具（EnergyPlus）和CFD工具（Ansys Fluent）之间的联合仿真框架，对PCM集成建筑环境进行建模，并将其预测精度与最流行的BES工具EnergyPlus进行比较。已对三个实验案例场景 1) 主动使用 PCM、2) 在自然对流期间被动使用 PCM 以及 3) 在强制对流期间被动使用 PCM 进行了建模，以进行预测精度评估。使用通用精度指数（均方根误差）以及时间温度变化进行比较。结果表明，对于强制对流下主动使用 PCM 和被动使用 PCM，所提出的联合仿真比 BES 工具具有更好的预测精度。为了对自然对流期间 PCM 的被动使用进行建模，建议使用 BES 工具。由于在极端气候条件下，主动使用和强制对流的 PCM 比被动使用 PCM 更有效，因此这项研究将有助于在极端气候条件下的早期建筑设计阶段使用 PCM 来模拟建筑环境。