Solar shroud design using Computational Fluid Dynamics

The Wireless Telecom Industry is moving into a new age wherein remote data transmission capabilities must meet the demands of versatile mobile devices. These needs will be met by powerful new innovations such as 4G and WiMax. The radio control devices that are responsible for delivering the newest technologies to end-users are subject to stricter requirements of power than predecessors in compact space. These scenarios compel an increase in power density. Radio control units need to be relatively of the same size but deliver far more power. In addition to these internal heat sources, external solar loading comes as a natural consequence of standard outdoor telecom installations. Direct sunlight induces a heat flux onto as many as three sides of an outdoor device. The thermal management of the resulting system requires a simple yet effective solution against solar loading the device while allowing for adequate air flow. In this paper, we examined the benefits of a solar shroud placed over a high-powered radio control unit combined with 12 different vent configurations installed on the surface of the shroud using Computational Fluid Dynamics (CFD). Natural convection cooling methods don´t require fans or pumps and hence are low maintenance and bear a low initial cost. The simulations were conducted under natural convection conditions. Both the flow and thermal phenomena was examined in the quest for optimal design. One of the benefits of having performed this analysis in a CFD environment was being able to examine the relationship between the mass flow of air through the primary heat sink and the corresponding drops in temperature levels at the internal heat sources. In this study, we were able to reduce the board temperature by 10%. The results suggested that external slat designs provided the lowest resistance to natural convection air flow and delivered the largest reduction in board temperature.