Jet impingement cooling was studied in a simulated rotating gas turbine blade, focussing the effects of Coriolis and centrifugal forces on new impingement-cooling configurations. The experiments were performed on two test models, namely two-pass rotating rectangular channel and one-pass rotating rectangular channel. Rotation-induced Coriolis and centrifugal forces deflected the jets away from the walls and caused characteristically different flow and heat transfer patterns in the impingement channels.;The first section of this dissertation studied impingement cooling in rotating two-pass rectangular channels. Jet Reynolds numbers and rotation numbers varied from 4 x 103 to 1 x 104 and 0 to 0.0133, respectively. Rotation-induced Coriolis and centrifugal forces decreased the Nusselt number values 20 and 25% in the impingement channels and turn region, respectively. Nusselt number values in the turn region were 60% higher when compared with those in the impingement channels for higher flow rates.;The second section investigated the effect of angled ribs (45-deg) in non-rotating and rotating impingement-cooled blades. Secondary flow produced by angled ribs and rotation interacted with each other and developed a new heat transfer pattern that is different from those produced by angled ribs or by rotation alone. As the jet Reynolds number increased from 4 x 103 to 1 x 104, the ratios of channel averaged ribbed-to-smooth surface Nusselt numbers increased from 13 to 47% for the nonrotating test. For the rotating test, however, these ratios changed from 9 to 44% as the jet Reynolds number increased. Rotation decreased the Nusselt number values up to 20% in the ribbed impingement channels.;The final section measured heat transfer coefficients in rotating one-pass rectangular channel under low jet velocities. Low jet velocities provided inadequate cooling and generated low heat transfer rates under non-rotating condition. This design could not simulate the flow and heat transfer conditions of an impingement-cooled high temperature gas turbine blade. Rotation generated strong secondary flow and enhanced the heat transfer rate from the walls. As rotation speed increased from 325 to 650 rpm at Rej = 1.6 x 104, the ratio of rotation to non-rotation Nusselt numbers increased from 1.3 to 2.5.
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机译：在模拟的旋转燃气轮机叶片中研究了射流冲击冷却，重点研究了科里奥利力和离心力对新型冲击冷却结构的影响。实验是在两种测试模型上进行的，即两遍旋转矩形通道和单遍旋转矩形通道。旋转引起的科里奥利力和离心力使射流偏离壁面，并在撞击通道中引起特征性的不同流动和传热方式。本论文的第一部分研究了旋转两通矩形通道中的撞击冷却。 Jet雷诺数和旋转数分别从4 x 103到1 x 104和0到0.0133。旋转引起的科里奥利力和离心力分别使撞击通道和转向区域的努塞尔值分别降低了20％和25％。与更高流量的冲击通道相比，转弯区域的Nusselt值高60％。第二部分研究了非旋转和旋转冲击冷却叶片中成角度的肋骨（45度）的影响。由成角度的肋骨和旋转产生的二次流彼此相互作用，并形成了一种新的传热模式，该模式不同于由成角度的肋骨或单独旋转产生的传热模式。随着射流雷诺数从4 x 103增加到1 x 104，对于非旋转测试，通道平均带肋与光滑表面Nusselt的比率从13％增加到47％。但是，对于旋转测试，随着射流雷诺数的增加，这些比率从9％变为44％。旋转降低了肋状冲击通道中的Nusselt值，最高可达20％。;最后一节测量了在低射流速度下旋转的单程矩形通道中的传热系数。在非旋转条件下，低射流速度提供了不足的冷却并产生了低传热率。该设计无法模拟冲击冷却的高温燃气轮机叶片的流动和传热条件。旋转产生强大的二次流并提高了壁的传热速率。当Rej = 1.6 x 104时，转速从325 rpm增加到650 rpm时，旋转与非旋转Nusselt数的比值从1.3增加到2.5。
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