Fig. 1. Schematic diagram of experimental system

Fig. 2. Distribution diagram of thermocouple positions

Fig. 3. Temperature oscillation of heat pipe operation (color online)

Fig. 4. Variation of heat pipe temperature and heating power (color online)

Fig. 5. Temperature oscillation at the end of heat pipe start-up (color online)

Fig. 6. Heat transfer coefficient of evaporation section in different operating regions of heat pipes (color online)

Fig. 7. Heat transfer coefficients of heat pipe evaporation section at different liquid levels

Fig. 8. Heat transfer coefficients of heat pipe evaporation section with different mesh sizes

Fig. 9. Comparison of experimental data with model for evaporator heat transfer coefficient (color online)