Topology optimisation of passive coolers for light-emitting diode lamps

This work applies topology optimisation to the design of passive coolers for light-emitting diode (LED) lamps. The heat sinks are cooled by the natural convection currents arising from the temperature difference between the LED lamp and the surrounding air. A large scale parallel computational framework is used to perform topology optimisation for minimising the temperature of the LED package subjected to highly convection-dominated heat transfer. The governing equations are the steady-state incompressible Navier-Stokes equations coupled to the thermal convection-diffusion equation through the Bousinessq approximation. The fully coupled non-linear multiphysics system is discretised using stabilised trilinear equal-order finite elements and solved using Newtons method and a multigrid-preconditioned iterative method. Topology optimisation is carried out using the density-based approach. The optimisation results show interesting features that are currently being incorporated into industrial designs for enhanced passive cooling abilities.