Channel flow modeling of impingement cooling of a rotating turbine blade

Abstract

Local heat transfer distributions in impingement cooling have been measured by Kreatsoulas [1] and Preiser [2] for a range of conditions which model those in actual turbine blades, including the effects of rotation. These data were reported as local Nusselt numbers, but referred to coolant supply conditions. By means of a channel flow modeling of the flow in the supply and impingement passages, the same data are here presented in terms of local Nusselt number distributions such as are used in design. The results in this form are compared to the nonrotating impingement results of Chupp [3] and to the rotating but non-impingement results of Morris [4]. Rotation reduces the mean Nusselt numbers from these found by Chupp by about 30 percent, and introduces important radial variations which are sensitive to rotation and to leading edge stagger angle.