旋转盘换热研究准则系统的确定

Determination of Similarity Criteria for Flow and Heat Transfer of Rotor-Stator Disks System

通过引入特征温差 qr R/λD,对控制转静系旋转盘腔内流动与换热的微分方程组进行了无量纲化 ,得到了研究转静系旋转盘腔内换热研究的准则系统。确定了涡轮盘冷却研究的主要研究内容和影响因素 :除盘面对流换热的努赛尔特数外 ,还应包括反映涡轮盘总体温度水平的无量纲过余体平均温度和反映转盘径向热应力大小的无量纲径向温差 ,借助于涡轮叶片冷却效果的概念 ,给出了涡轮盘冷却效果的表达式。

Characteristic parameters, q rR/λ D are introduced as the temperature difference to non dimensionalize the governing equations,and then the similarity criteria for flow and heat transfer of rotor stator disks system are established.It is concluded that the study of cooling effects in the turbine disks should comprise not only Nusselts number for disk surface convective heat transfer,but also the non dimensional excessive averaged body temperature for total disk temperature level and the non dimensional radial temperature difference for the disk radial thermal stress.With resort to the concept of turbine blade cooling efficiency,an expression is derived for calculating the cooling efficiency of a turbine disk.