相变温控导热增强的多孔金属梯度优化设计

高孔隙率金属多孔材料比表面积大、导热性能好且掺混能力强，是理想的相变换热导热增强体材料。增材制造能够精准制备几何高度复杂的微结构，为多孔金属任意梯度设计提供可能。为实现更高的相变换热性能，建立了多孔金属相变温控导热增强的梯度优化设计模型。该优化模型以孔隙率分布为设计变量，以多孔金属用量为约束，以关键位置的温度最低为设计目标，基于考虑相变过程的多孔介质两方程模型为分析方法，通过遗传算法对优化模型进行求解。通过与实验结果的对比，验证了分析方法的有效性。两个具体算例证实了梯度设计能够大幅度提高多孔金属介质导热增强的相变温控性能。

Gradient optimization of metal cellular material as thermal conductivity enhancer for phase-change temperature control

Metal cellular materials with high porosity is an ideal thermal conductivity enhancer because of their large specific surface area,high thermal conductivity,and strong mixing ability.Additive manufacturing is able to fabricate cellular materials with defined complex mesostructures including the gradient cellular structure.In this study,the gradient optimization model of cellular materials as a thermal conductivity enhancer for the phase-change temperature control is proposed.In the optimization model,the porosity is regarded as a design variable,the amount of the cellular consumed is considered as the constraint,and the minimum temperature at the key position is the design goal.The numerical method based on the two-equation model of cellular media considering phase-change is employed here and the optimization model is solved by the genetic algorithm.The effectiveness of the analytical model is verified by the comparison with the experimental results.Two special examples demonstrate that the enhanced performance of phase-change temperature control can be achieved by the gradient design of a metal cellular material as a thermal conductivity enhancer.