PERFORMANCE OF LIQUID COOLING HEAT EXCHANGERS FOR TELECOMMUNICATION EQUIPMENT

摘要

Thermal control of telecommunication equipment has one principle objective that is to maintain relatively constant component temperature equal to or below the manufacturer’s maximum specified service temperature. To solve this problem, many electric cooling applications involve liquid cooling of the components. Information for designing liquid cooling heat exchanger, which can be used in the field directly, is very limited in open literature. In this paper, four liquid cooling heat exchangers for telecommunication equipment were designed. The liquid-cooling heat exchangers had twelve rectangular channels with different flow paths of 1, 2, 4, and 12. Silicon rubber heater was attached on the front side to control the heat load to the heat exchangers. Heat input ranged from 293 to 800 W, and inlet temperatures of working fluid maintained at 25°C. The local heat transfer coefficients defined by the mean temperature on the back side of heat exchangers. The enhancement factor, which was defined as the ratio of the heat transfer enhancement factor to the pressure drop penalty factor, was employed to estimate the performance of the heat exchangers. Even though the pressure drop of the 4-path channel was higher than that of the 12-path channel heat exchanger, the enhancement factor of the 4-path channel heat exchanger was higher than that of the 12-path channel heat exchanger due to a higher heat transfer coefficient.