Thermal management of an led light engine for airborne applications

Rockwell Collins has recently developed a light engine, which uses four light emitting diodes (LEDs) as the light source, for a cockpit display system. Under worst case operating conditions, the local heat flux from these LEDs can be more than 1000 W/cm2. This paper describes the thermal management approach for the light engine and presents the results of finite element modeling. This modeling was used to assess various design aspects of the light engine to understand their effects on the overall thermal resistance. Thermal testing of a set of light engines was eventually found to be quite comparable to the modeling results, although a discrepancy between testing and modeling results did help to identify a manufacturing defect that occurred in some early prototype devices, which significantly increased their thermal resistance