Performance Characteristics of a Liquid-Metal Heat Pipe for igh-temperature Solar Thermal Devices Depending on the Operating Conditions

고온 태양열기기용 액체금속 히트파이프의 작동조건에 따른 성능 특성

Sodium heat pipe for high-temperature solar thermal application was manufactured and tested for transient and steady-state operations. Total length of the heat pipe was 650 mm and the outer diameter was 12.7 mm. Thermal performance was compared experimentally for two different cooling methods of the forced and the natural convection cooling in the heat pipe condenser. During the experiment, the maximum temperature was about 1300K, and different cooling methods were applied to the condenser region to charge the operating temperature. The effective thermal conductivity and the thermal resistance were investigated as a function of heat flux, heat transport length, and operating temperature.