Geometric Optimization of SLM-Printed AlSi10Mg Radial Heat Sinks: A Numerical and Experimental Approach for Natural Convection Conditions

The current study explores the thermal performance and geometric optimization of radial heat sinks manufactured through selective laser melting process of AlSi10Mg material, primarily intended for cooling applications in light-emitting diodes (LEDs). Few studies have systematically approached the geometric optimization of radial heat sink designs, particularly considering variable fin heights (both fin outer and fin inner height), in conjunction with other geometric parameters like fin length, fin thickness, and the number of fins tested across a broad spectrum of heat flux values. Through comprehensive experimentation and numerical simulations, the independent and combined impact of these considered key geometric parameters was investigated on the heat sink performance. The experimental design, guided by Response Surface Methodology, encompasses a wide range of heat flux levels, varying from 300 to 1800 W/m2, to ensure the broad applicability of the findings. The results underscore the significance of fin thickness, which notably influences the base temperature of the heat sink, particularly at higher heat flux levels. The interaction between heat flux and fin length also plays a pivotal role in base temperature control, with additional fins contributing to lower temperatures. Furthermore, it was revealed that higher fin outer heights, combined with lower fin inner heights, lead to superior heat sink performance, aligning with practical LED cooling requirements. The optimization process results in configurations that consistently maintain base temperatures below the critical 70 °C threshold, thus contributing to effective thermal management in LED devices.