Investigation of thermal characteristics of an LHP evaporator with heat sources having different heating surface areas

Abstract

The paper presents the results of investigation of thermal characteristics of a flat evaporator 10 mm thick with an active zone of 27 cm2 that is part of a copper–water loop heat pipe (LHP) intended for cooling systems of high-power electronic components. The investigation of the device was conducted in a horizontal position with heat sources having thermocontact surfaces of 9 cm2, 16 cm2 and 25 cm2 at heat load from 20 to 900 W. It is shown that the evaporator thermal resistance and the heat flux depend considerably on the value of the thermocontact surface of the heat sources. The minimum values of thermal resistance were, respectively, 0.033, 0.021 and 0.016 °C/W at heat fluxes of 100, 56.2 and 36 W/cm2. The temperature distribution over the evaporator surface with different heat sources has been obtained in analytical way.