管壳式相变蓄冷单元传热肋片拓扑优化设计

针对管壳式相变蓄冷单元传热肋片结构设计固化，概念设计缺乏理论指导，强化换热效果有限等问题，基于拓扑优化理论，构建二维管壳式相变蓄冷单元的物理模型并进行有限元分析；选取最终时刻平均温度为目标函数，以肋片材料体积占比为约束条件构建管壳式相变蓄冷单元二维肋片拓扑优化模型；对模型进行特征求解得到肋片清晰的拓扑轮廓以及动态演化特性。在上述研究基础上，进一步分析了不同肋片体积占比下所得优化拓扑构型的异同，得出20%的体积占比是综合考虑优化效果和成本的较优值。对比相同肋片体积分数下直肋单元与拓扑优化肋单元的蓄冷特性，结果发现，采用拓扑优化肋片的蓄冷单元中蓄冷速率较直肋提高了41.7%,最终时刻设计域的平均温度较直肋降低了3℃左右，从而验证了拓扑优化在相变蓄冷单元传热结构优化方面的优势。

Topology optimization design of heat transfer fins of shell-and-tube phase change cold storage unit

In view of the problems of solidification of the structure design of heat transfer ribs of shell and tube phase change cold storage unit, the lack of theoretical guidance in conceptual design, poor improvement of heat transfer enhancement and other problems, the physical model of the two-dimensional pipe shell phase change cold storage element was constructed and the finite element was analyzed based on the topology optimization theory, the average temperature at the final moment was selected as the target function, and the two-dimensional fin topology optimization model of the shell and tube phase change cold storage unit was constructed based on the condition of the proportion of the volume of the fin material. Besides, the similarities and differences of the optimized topological configuration obtained under the proportion of different fin volume were further analyzed, and the volume ratio of 20% is the better value of comprehensively considering the optimization effect and cost. Comparing the cooling characteristics of the straight fin unit and the topological optimization fin unit under the same fin volume fraction, it is found that the cold storage rate of the topologically optimized fin is increased by 41.7% compared with the straight fin, and the average temperature of the final design domain is reduced by about 3°C compared with the straight fin, thus the advantages of topology optimization in the heat transfer structure optimization of the phase change cold storage unit is verified.