Topology Optimization of Fins for Heat Sinks under Steady Heat Conduction

There is a copper electronic circuit located in a steel shell, with the aluminum fins used for heat dissipation above the shell. For this heat sinks, topology optimization design of the fins is carried out based on ANSYS Workbench, and the calculation results have been obtained for different volume retention rates. Usually, the heat dissipation effect is mainly determined by the heat dissipation surface the fins, and the larger the surface area, the better the heat dissipation effect. A smaller volume retention rate can increase the heat dissipation surface of the fins, but it is also prone to create the sharp and intermittent topological structures, which are very unfavorable for subsequent 3D printing. Taking into account some factors such as heat dissipation efficiency and processing difficulty, a topology optimized structure for heat dissipation fins with a volume retention percentage of 40% has been obtained, whose heat dissipation surface is smooth and continuous. Compared with the original heat sinks, the temperature of the central electronic circuit decreases from 106.5 ℃ to 67.5 ℃, and the temperature of the fins decreases from 91.7 ℃ to 53.7 ℃, which indicates that a good heat dissipation effect is obtained. The mass of the heat sinks has decreased by 21% to save a lot of aluminum materials. Due to the irregular structure of heat dissipation sinks, the traditional subtractive manufacturing ways are not suitable for processing; however, the additive manufacturing technology can fabricate the complex and irregular structures, 3D model of the same size as the heat sinks is printed by using fused deposition modeling (FDM) technology.