Thermal energy storage (TES) is extensively applied in production and daily life. As a basic work, we designed a single tank phase change TES domestic hot water system using night valley power. Based on the single tank TES experimental platform, a 2D numerical model of the system was established. To optimize the performance of a single tank TES system, the effect of heat transfer fluid (HTF) inlet velocity and temperature on the heat release of the storage tank was analyzed based on simulation. The enhanced heat transfer effect of the radial cascade system and axial cascade system was also compared. The results showed that 0.8 m/s is the optimal HTF inlet velocity in the calculation range. The rule of the heat release about the HTF inlet temperature just meets the different hot water requirements in winter and summer. The heat release capacity of the radial cascade system and axial cascade system is higher than that of the conventional single-stage system, and the proportion of latent heat release in radial cascade is larger. This study will provide theoretical guidance for the optimal design of the single tank TES domestic hot water system in the future.

热能存储（TES）广泛应用于生产和日常生活中。作为基础工作，我们设计了使用夜谷电源的单槽相变TES家用热水系统。基于单槽TES实验平台，建立了系统的二维数值模型。为了优化单槽TES系统的性能，在模拟的基础上分析了传热流体（HTF）入口速度和温度对储罐散热的影响。还比较了径向级联系统和轴向级联系统的增强的传热效果。结果表明，在计算范围内，最佳HTF入口速度为0.8 m / s。关于HTF入口温度的放热规律恰好满足冬季和夏季的不同热水需求。径向级联系统和轴向级联系统的散热能力高于常规单级系统，并且径向级联中潜热释放的比例较大。该研究将为今后单槽TES家用热水系统的优化设计提供理论指导。