A CFD analysis of an electronics cooling enclosure for application in telecommunication systems

This paper presents results of CFD analysis of an electronics cooling enclosure used as part of a larger telecommunication radar system. An original cooling enclosure was simulated using Flotherm which results were taken as the benchmark thermal performance. It was found that the operating temperature of one of the Radio Frequency (RF) components will exceed the design temperature limit of the PCB. A solution involving a re-design of thermal spreading arrangements using a 3 mm thick copper shelf and a Vapour Chamber (VC) heat pipe was found to bring the operating temperatures of all RF components within the specified temperature limits. The use of a VC, in particular, reduced the 60 W RF component steady state temperature by an average of 5.4 °C. The study also shows that increasing the finned heat exchanger cooling air flow rate can lower further the RF components temperature though at the expense of increasing energy consumption of the fan.

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