关键词: 铯热管, 传热, 两相流, 启动性能, 均温性

Abstract: Heat pipes with sodium and potassium as working fluids has been used in medium-high temperature heat pipes. There are few reports on the startup and heat transfer performance of cesium heat pipe. This study processes a medium temperature cesium heat pipe. The heat flux is controlled by the high frequency heating system and the wall temperature is measured by the data acquisition system to study its performance. The results show that the temperature revolutions at startup stage are similar for cesium and sodium heat pipe when heat flux q=18.04w/cm2; The maximum temperature difference between the adiabatic section and the evaporation section reaches 30℃ , which shows the phenomenon of the sonic limitation. Meanwhile, the experimental data proves the calculation of the transition temperature with Kn=1 is more accurate for cesium heat pipe. In addition, heat dissipation styles have great influence on the starting speed and stable temperature of the heat pipe, but no influence on the transition temperature. When the heating power is below 67W /cm2 with the stable temperature less than 586℃, the maximum temperature difference along the whole tube is lower than 7℃, and the effective length is 100%, showing excellent heat exchange performance and temperature uniformity.

Key words: cesium heat pipe, heat transfer, two phase flow, startup performance, temperature uniformity