A novel design of biomimetic snowflake heat sink by topology optimization verified by experiments

The purpose of this paper is to perform coupled topology optimization of the temperature field and flow field on the thermal sink topology of the imitated snowflake, aiming to reduce the pressure drop as much as possible while improving heat exchange efficiency. Two multi-objective optimization functions—minimizing both the average temperature and pressure drop, and minimizing both the temperature difference and pressure drop—were used in a pseudo-3D topology optimization, yielding two different channel structures, M1 and M2. Numerical analysis shows that the topology-optimized channels M1 and M2 offer better thermal performance than the conventional snowflake straight-through channel M3. Compared with M3, the thermal resistance of M1 and M2 was reduced by 27.5 % and 31.5 % respectively, while the temperature difference was reduced by 45.7 % and 52.4 % respectively. Although the pressure drop increased slightly, it is justified by the significant improvement in heat exchange capacity. Among them, the pressure drop of M2 is approximately 21.3 % lower than that of M1, making it the superior design. Finally, experiments were carried out to validate the accuracy of the numerical simulations, with the maximum relative error in temperature being less than 1.3 % and the maximum relative error in pressure drop less than 6.7 %.