TY - JOUR TI - Design and verification of ultra-high temperature lithium heat pipe based experimental facility AU - Hu Chongju AU - Yu Dali AU - He Meisheng AU - Li Taosheng AU - Yu Jie JN - Thermal Science PY - 2022 VL - 26 IS - 4 SP - 3413 EP - 3426 PT - Article AB - Lithium heat pipe has broad applications in heat pipe cooled reactors and hypersonic vehicles due to its ultra-high working temperature which is around 1700 K. In this paper, a lithium heat pipe based experimental facility has been designed to test the heat transfer performance of the lithium heat pipe. A simplified mathematical model of heat pipe has been implemented into a CFD approach, which is used to verify the design of lithium heat pipe and its experimental facility. Results showed that the CFD approach is in good agreements with some well-known existing models and experimental data, and deviation between the results is within 5% range. The adjustment range of mixed gas thermal resistance and cooling water flow rate was obtained by analyzing the effects of different cooling conditions on the performance of the experimental facility. It is necessary to ensure the cooling water flow rate is above 0.11 Lph to prevent water boiling when the heating power is 10 kW around, and the optimal proportion of helium is 70-90%. The operation characteristics of the lithium heat pipe under unsteady-state with varying heating power were simulated numerically. The results show that the proportion of helium must be less than 60% for normal operation of the lithium heat pipe. This work provides a reference and numerical verification for the design of lithium heat pipe based experimental facility, which can be used to reveal the heat transfer mecha¬nisms of the lithium heat pipe during the experiment.