Thermal performance and multi-objective optimization of thermosyphon heat sinks with rectangular radial fins for high power LED lamps cooling

Abstract

The thermosyphon heat sinks with rectangular radial fins are presented for heat dissipation of high power LED lamps in this paper. The thermosyphon is made of copper, which includes the evaporator with 60 mm length and condenser with 180 mm length. The rectangular radial fins with 2 mm thickness and 180 mm height are connected to the external surface of the condenser. The influence of fin number (10–50) and fin length (30–90 mm) on the thermal performance is revealed by the partial derivative of temperature to mass. A multi-objective optimization of the thermosyphon heat sink considering the thermal performance and mass is performed to obtain the Pareto optimal thermal performance using Response Surface Methodology and non-dominated sorting genetic algorithm II. The results show that the effects of the fin length (30–60 mm) and fin number on the thermal performance and the mass are significant, respectively. The Pareto optimal solution is obtained of the maximum temperature (67.7 °C), thermal resistance (0.45 K/W) and mass (1.74 kg) corresponding to the number of fins (23) and fin length (59 mm), which releases the heat of 92 W. It provides further guidelines for designing thermosyphon heat sinks in high power LED lamps cooling.