凹坑板式空气预热器的传热特性及多目标优化

Heat Transfer Performance of a Plate Air Preheater with Dimpled and Multi-Objective Optimization

摘要:

以全焊接型凹坑板式空气预热器为对象，基于最优设计试验方案，运用Workbench Fluent软件数值模拟凹坑板片特征结构参数对传热流阻性能的影响。基于参数敏感度分析，得到单因素作用下对传热流阻性能的影响程度为凹坑的纵向间距＞长轴＞横向间距＞深度。基于响应曲面法分析，得到多因素协同作用时，凹坑之间的结构参数横纵距对性能影响比凹坑自身的结构参数深径比大。基于遗传算法以摩擦因子f最小、努塞尔数Nu与综合换热因子J_F最大为优化目标，得到给定范围内的3组较优结构组合。

Abstract:

Taking the fully welded dimples plate air preheater as the object， the Workbench Fluent software is used to numerically simulate the influence of the characteristic structure parameters of the dimpled plate on the heat transfer and flow resistance performance by orthogonal experiment. Based on the parameter sensitivity analysis， the effect of single factor on the heat transfer flow resistance performance is obtained： longitudinal spacing of dimpled > long axis > horizontal spacing > depth. Moreover， the fact is obtained that under the synergistic effect of multiple factors， the structural parameters horizontal and longitudinal distance have a greater impact on performance than the depth-diameter ratio of the dimpled based on the analysis of the response surface method. Furthermore， three sets of better structural combinations within a given range are obtained based on the genetic algorithm， with the smallest friction factor， and the largest Nusselt number and comprehensive heat transfer factor as the optimization objectives.