高旋转数下不同通道转角梯形带肋回转通道的换热特性

Heat transfer characteristics in two-pass rib-roughened trapezoidal channel at high rotation number with different model orientation angles

为研究截面形状和旋转效应对高压涡轮动叶内部冷却通道换热的影响,对雷诺数为10 000~50 000,旋转数为0~2.09,通道转角为0°、22.5°、45°的带直肋双流程梯形截面通道换热特性进行了实验研究。结果表明:静止状态下,在第一通道,梯形通道后缘换热强于前缘;在第二通道,前、后缘换热区别不大,后缘的换热略强于前缘。旋转状态下,对0°通道转角,随旋转数的增大,第一通道的后缘面换热仍强于前缘面和外侧面,且差异更明显;第二通道前缘换热相对后缘增强。在较高旋转数(旋转数大于1)时,0°通道转角工况的换热最强,45°转角最弱。

In order to study the effects of rotation on a real-shaped internal cooling channel in the high pressure turbine blade,the heat transfer characteristics of a two-pass trapezoidal channel with vertical ribs were studied experimentally,with Reynolds numbers range of 10 000-50 000,rotation number range of 0-2.09 and the model orientation angles of 0°,22.5°and 45°.The results indicated that：for the stationary case,the heat transfer at thetrailing wall was stronger than that at the leading wall in the first channel,but it was only slightly larger in the second channel.For the rotating case with the model orientation angle of 0°to the axis of rotation,as the rotation number increased,the heat transfer difference between the trailing wall and the leading wall became larger in the first channel,while the heat transfer at the leading wall gradually became stronger than that at the trailing wall in the second channel.At a high rotation number（rotation number was more than 1）,the heat transfer was the largest for the case with 0°model orientation angle,and the smallest for the case with 45°model orientation angle.