Experimental research on thermal characteristics of loop heat pipe with liquid guiding holes

In the present study, the thermal characteristics of a loop heat pipe (LHP) with four lines of liquid guiding holes (LGHs) distributed along the bayonet were experimentally investigated. The loop was made of aluminum with nickel wick, and the working fluid was water. Experiments were conducted on the start-up, transient performance and the temperature oscillation of the LHP with LGHs at the heat loads from 70 W to 220 W, and the tilt angles between the evaporator and compensation chamber (CC) from 0° to 10°. It was found that with the increase of tilt angle from 0° to 10°, the working temperature of the LHP increases by approximately 4.6-8.2% for the heat load less than 180 W, while decreases by 3.5% for the heat load over 180 W. Obvious temperature oscillations of every component of the LHP, especially the condenser inlet, were observed when the temperature of CC was changed and the tilt angle was decreased from 5° to 0°. Under the present experimental conditions, the thermal resistance of the LHP ranges from 0.31 to 0.59 °C/W.