Optimization and experimental verification of microchannel heat sink based on heat transfer and flow balance regulation

The heat transfer performance and flow performance of microchannel convective heat transfer processes are usually mutually constrained. However, we expect microchannel heat sinks to have both excellent heat transfer and good fluidity. In order to achieve a balance between heat transfer and fluidity, we established an optimization objective function of a complex network structure based on the linear programming method. This composite objective function included both the entransy dissipation rate model to express the heat transfer performance of the fractal microchannel heat sink and the pump power model to express its flow performance. Under the same initial values and constraints, we optimized the objective function. Finally, the comprehensive performance of the optimized structure (OPTS) and the randomly designed initial structure was compared through experiments. The experimental results show that the comprehensive performance of the OPTS was always better than the initial design structure (INDS) under any conditions, and the performance of the optimized structure with fewer fractal levels was better. Within the scope of the study, the average comprehensive performance of the OPTS was improved by a minimum of 14% and a maximum of 30% relative to the INDS. This validates the rationality of the optimization method proposed in this study. We have theoretically and experimentally solved the active optimization problem of how many levels of fractal structure should be designed in a constant space and what the channel size of each level is when the heat sink has optimal performance.