Abstract:

Based on the bi-objective topology optimization method, five microchannel structures with different aspect ratios of the design domains were optimally designed, and the optimal design variable field, temperature field and pressure field under each working condition were obtained. On this basis, the effects of different Reynolds numbers on the microchannels were investigated, and the theoretical analysis and comparison of microchannels with different structures were carried out by combining the field synergy principle and entransy dissipation theory to provide a theoretical basis for optimizing the microchannel structures. The findings demonstrated that when the Reynolds number rose in the laminar flow region, the complexity of the topological flow channels also rose. The average temperature decreased, the Nu rose, the inlet and outlet pressure drop gradually increased, the PEC gradually decreased, the field synergy number increased, the pressure drop synergy angle gradually increased, the entransy dissipation increased, and the flow heat transfer characteristics of each heat dissipation channel tended to be optimized. The investigation of microchannels with various topologies structures revealed that the microchannels with a design domain aspect ratio of 25/64 had the best synergy effects of velocity-pressure gradient and velocity-temperature gradient, the best heat transfer effect, and the best flow characteristics.

Key words: microchannels, bi-objective topology, field synergy principle, entransy dissipation, numerical simulation, optimization

摘要：

基于双目标拓扑优化方法，对五种不同设计域长宽比的微通道结构进行了优化设计，获得各工况下的优化设计变量场、温度场及压力场。在此基础上，研究了不同Reynolds数对散热通道的影响，并结合场协同原理和耗散理论对不同结构的微通道进行理论分析和比较，为优化微通道结构提供理论依据。结果表明：在层流范围内，随着Reynolds数增加，拓扑流道变得更加复杂，域内平均温度逐渐降低，Nu增大，进出口压降逐渐升高，PEC逐渐减小，场协同数增大，压降协同角逐渐增大，耗散增大，各散热通道的流动传热特性趋于优化。在不同拓扑结构微通道的探究中，设计域长宽比为25/64微通道的速度场与温度场协同效果及速度场与压力场协同效果最好，传热效果最好，流动特性最优。

关键词: 微通道, 双目标拓扑, 场协同原理, 耗散, 数值模拟, 优化