Abstract The performance of a latent heat storage unit (LHSU) greatly rely on the melting/solidification rate which in turn affected by the orientation of LHSU. The orientation of the LHSU greatly influences the natural convection phenomenon, thereby affects the melting behavior of PCM. The present study is aimed at investigating the performance of a shell and tube LHSU positioned at various inclinations. Four inclinations are considered from vertical to horizontal position. Lauric acid is chosen as PCM with a melting range of 43.45°C–49.94 °C. Both melting and solidification characteristics are analyzed with the help of energy and exergy analyses (PCM average temperature, melt fraction, energy and exergy efficiency, energetic and exergetic effectiveness). From the experimental results, it is observed that the orientation has a major influence on the melting phenomenon and solidification is unaffected by the orientation of LHSU. Melting rate is observed to be higher for horizontal configuration till the PCM in the upper half portion is melted, however total melting time is observed to be less for vertical configuration. In addition, exergy efficiency is found to be higher for vertical configuration while melting, whereas for discharging process the exergy efficiency is same for all the inclinations.

中文翻译：

---

位于不同方向的潜热蓄热单元的能量和火用分析——一项实验研究

摘要 潜热蓄热单元 (LHSU) 的性能在很大程度上取决于熔化/凝固速率，而后者又受 LHSU 取向的影响。LHSU 的取向极大地影响了自然对流现象，从而影响了 PCM 的熔化行为。本研究旨在研究位于各种倾斜度的壳管式 LHSU 的性能。从垂直位置到水平位置考虑了四种倾斜度。选择月桂酸作为 PCM，熔点范围为 43.45°C–49.94°C。借助能量和火用分析（PCM 平均温度、熔体分数、能量和火用效率、能量和火用效率）分析熔化和凝固特性。从实验结果来看，据观察，取向对熔化现象有主要影响，凝固不受 LHSU 取向的影响。观察到水平配置的熔化速率更高，直到上半部分的 PCM 熔化，但观察到垂直配置的总熔化时间较短。此外，发现垂直配置在熔化时的火用效率更高，而对于放电过程，所有倾斜度的火用效率都相同。