Measurements in the Transition Region of a Turbine Blade Profile Under Compressible Conditions

Abstract

The transition region plays a critical role in the design of turbine blades, as it is accompanied by higher losses (1) and higher heat transfer rates (2). Most of the transition onset and length correlations have been developed from incompressible measurements with only a limited number of investigators addressing the effect of Mach number. Narasimha (3) investigates the Reθ(ST) and concludes that it increases with Mach number; thereby delaying transition onset. In contrast, Schook et al. (4) found the Reθ(ST) from compressible measurements to be consistently lower than that correlated by Mayle (5) for the incompressible range. Thus the experimental evidence is contradictory.