This study investigated the heat transfer characteristics of a Closed-End Thermosyphon (CE-TPCT) made of copper tubes with 5.5 mm diameter. The experiments were conducted with working substance filling rates of 0%, 30%, 50%, and 70% of the volumetric evaporator section, the evaporator temperatures of 50, 70, and 90 °C and inclination angle of 90°. The lengths of the evaporator section, adiabatic section and condenser section used in the experiments were 60 mm, the distance between the compartments was 5Di. Water was the working substance used in the experiments with the mass flow rate of the water inlet at the condenser section of 0.25 L/min. The water inlet temperature at the condenser was 20 °C. Obtained results were compared with convectional Thermosyphon (TPCT) which was tested under the same conditions. The results showed that CE-TPCT at the filling rate of 70% at the evaporator section volume had an average heat transfer rate and average heat flux of 140.72 ± 4.92 W and 33.41 ± 1.16 kW/m², respectively, throughout the experiment. These results were higher than the other tested parameters. The highest heat transfer rate of 220.32 ± 7.71 W and average heat flux of 52.31 ± 1.83 kW/m² were recorded at the evaporator temperatures of 90 °C. The experiment also showed a lower average total thermal resistance throughout when it was compared with other test parameters which was equal to 0.547 °C/W. This resulted in high heat transfer coefficients and relative thermal efficiency of 625.11 W/m²·°C and 1 respectively, the highest value of all studied experimental variables. When the maximum heat flux results between CE-TPCT and TPCT under the same condition parameters were compared, CE-TPCT demonstrated a higher heat flux value of 18.24%. The heat transfer characteristics of the CE-TPCT obtained from this study provides an alternative application choice for various types of heat exchanger that can reduce energy consumption in the future.

本研究调查了由直径为 5.5 毫米的铜管制成的封闭式热虹吸管 (CE-TPCT) 的传热特性。实验采用容积式蒸发器段的工质填充率为0%、30%、50%和70%，蒸发器温度为50、70和90°C，倾角为90°进行。实验中使用的蒸发器段、绝热段和冷凝器段的长度为60 mm，隔室之间的距离为5Di。实验所用工质为水，冷凝段进水口质量流量为0.25L/min。冷凝器的进水温度为 20 °C。将获得的结果与在相同条件下测试的对流热虹吸 (TPCT) 进行比较。²分别贯穿整个实验。这些结果高于其他测试参数。在 90 °C 的蒸发器温度下记录的最高传热率为 220.32 ± 7.71 W，平均热通量为 52.31 ± 1.83 kW/m ²。与等于 0.547 °C/W 的其他测试参数相比，该实验还显示出较低的平均总热阻。这导致了高传热系数和 625.11 W/m ^{2 的}相对热效率·°C 和 1 分别是所有研究的实验变量的最高值。当比较相同条件参数下 CE-TPCT 和 TPCT 之间的最大热通量结果时，CE-TPCT 表现出更高的热通量值，为 18.24%。从本研究中获得的 CE-TPCT 的传热特性为各种类型的换热器提供了一种替代应用选择，可以在未来降低能耗。