Thermal management design of an upgraded LED Rail Signal Lamp Challenge The client had upgraded to a new PCB and processors in their product, but this led to components overheating. A new thermal management design was needed to address this issue and provide sufficient present and future cooling. Solution Informed by experimentally-validated CFD simulations, two improved heat sinks were designed to be incorporated in the product. A more thermally conductive alloy was selected to improve performance. This new design was prototyped and tested by the client. The results were in good agreement with modelled predictions. Details Our client had recently updated the printed circuit board (PCB) and processors controlling their LED rail signal lamp product. These components generated more heat and CFD modelling predicted that the current design would fail to maintain components below maximum operating temperatures. The lamp had to comply with stringent regulations and operate in a wide ambient temperature range. Any new design had to meet these requirements while fitting in the same housing. Based on thermal management experience, CEAD chose to investigate the use of die-cast aluminium alloy heatsinks operating with natural convection. A thermal study of the original design was performed using CFD software and compared to experimental data in order to understand the accuracy of any temperature predictions. Very good agreement was found between predicted and experimental temperatures. Multiple iterations of heat sink designs were simulated, investigating each heat sink independently as well as the full lamp assembly. Modelled results showed the new design could reduce key component temperatures below maximum operating temperatures. The client desired further cooling, so alternative aluminium alloys were modelled and showed even better performance. New CAD designs for the heat sinks were passed on to the client for prototyping and testing to validate the CFD before investing in tooling for volume manufacture. Excellent agreement was found, and the client progressed into manufacture of the improved product.