Numerical investigation and experimental verification of topological optimized double-layer mini-channels

Double-layer micro/mini channel heat sinks have great potential in the thermal management for integrated chips. In this work, two bi-objective optimization design of mini-channels is implemented using the variable density topology optimization method to get two topological single-layer mini-channel heat sinks (SL-MHSs). Among them, the SL-MHS obtained with the minimization of average temperature and power dissipation as the optimization objectives is named S1, while the SL-MHS obtained with the minimization of temperature variance and power dissipation as the optimization objectives is named S2. Then, S1 and S2 are used as the upper/lower layer of the double layer mini channel heat sink (DL-MHS), respectively. Therefore, four different topological DL-MHSs including D11, D12, D21 and D22 are achieved by assembling S1 and S2. Subsequently, the flow and thermal characteristics of the four topological DL-MHSs and conventional straight DL-MHS (C1) are studied numerically. The results show that when Re = 315, compared with C1, the maximum temperature of the sub-strate of the topological DL-MHSs (D11, D12, D21 and D22) can be respectively reduced by 17.0,16.6, 14.0 and 13.6 K, while the Nusselt number can be improved by 27.3%, 26.6%, 27.1% and 26.4%, respectively. Addi-tionally, the total thermal resistance is also reduced at least 20%. However, although topological DL-MHSs produce higher pressure drop penalty, the PEC values of topological DL-MHSs are always greater than 1, which indicates that the new topological DL-MHSs is meaningful. Finally, the flow and thermal characteristics of the best one D11 are investigated experimentally. The simulated results agree well with the experimental results.

Automated summary

In this study, bi-objective optimization design of mini-channels is implemented to obtain single-layer mini-channel heat sinks (SL-MHSs), which are then used as upper and lower layers to assemble double-layer mini channel heat sinks (DL-MHSs). Numerical results show that the new DL-MHSs can significantly reduce the maximum temperature, increase the Nusselt number, and decrease the total thermal resistance.