An R1234ze(E) loop heat pipe with flat-plate evaporator for cooling electronic devices

Abstract

With the development of high power electronic devices, the failure problem caused by the high temperature must be solved by a reliable cooling solution. A solution for cooling electronic equipment was proposed in this paper. Two loop heat pipe systems with flat-plate evaporator were designed. The effect of a new refrigerant, R1234ze(E), on the thermal performance of the loop heat pipe was investigated. Two cooling methods were designed to achieve different cooling requirements, namely liquid-condenser and air-condenser respectively. The reliability of the solution had been fully verified. When the temperature of the heat source was kept below 75 °C, the heat load that could be cooled by the two condensing methods is 150 W (9.8 W/cm2). The largest heat load of the liquid-condenser could even reach 270 W (16.9 W/cm2) under gravity assistance. For the air-condenser, the normal operating range was 10 W–150 W while the working power of the fan was 20 W. Under different operating conditions, the system responded quickly and without any failures. The minimum total thermal resistance of liquid-condenser LHP and air-condenser LHP was 0.307 °C/W and 0.135 °C/W, respectively. These two LHPs meet the cooling needs of electronic devices and can effectively alleviate the thermal problems of electronic devices.