板翅式换热器传热、阻力多目标权衡优化

Multi-Object Tradeoff Optimization of Heat Transfer and Fluid Friction for Plate-Fin Heat Exchanger

本文利用NSGA-Ⅱ算法对板翅式换热器中流体的传热和阻力分别引起的熵产数和(?)耗散数进行了多目标权衡优化。使传热和压降这两个相互矛盾的目标函数同时达到最优,并对帕累托前沿解域进行了LINMAP(多维偏好分析的线性规划)决策,最后对比了两种适值函数的优化结果。结果显示:换热器结构在11个自由度,并满足较小的熵产数或■耗散数的条件下,相比单一目标函数压降最大减少73.65%,成本最多节省1.61%;在相同换热效率下,煨耗散法优化得出的总成本比熵产法减少0.01%。

In this paper multi-object optimization is carried out for plate-fin heat exchanger（PFHE）using NSGA- II algorithm,which adopts the entropy generations or entransy dissipations caused by heat transfer and fluid friction as object functions These objectives are optimized simultaneously in a multi objective optimization process which balances the two conflicting objectives.The LINMAP decision-making method is applied to Pareto frontier to obtain the final results.Under the condition that heat exchanger structure has 11 degrees of freedom and meets the smaller entropy generation or entransy dissipation,the results show that pressure drop achieves in a maximum reduction of 73.65%,and the cost saves up to 1.61%compared with a single objective function.The total cost of entransy dissipation method is 0.01%lower than that of entropy generation method under the same thermal efficiency.