A detailed experimental investigation was conducted into the interaction of a convected wake and a separation bubble on the rear suction surface of a highly loaded low-pressure (LP) turbine blade. Boundary layer measurements, made with 2D LDA, revealed a new transition mechanism resulting from this interaction. Prior to the arrival of the wake, the boundary layer profiles in the separation region are inflexional. The perturbation of the separated shear layer caused by the convecting wake causes an inviscid Kelvin-Helmholtz rollup of the shear layer. This results in the breakdown of the laminar shear layer and a rapid wake-induced transition in the separated shear layer.
The Transition Mechanism of Highly Loaded Low-Pressure Turbine Blades
Contributed by the International Gas Turbine Institute and presented at the International Gas Turbine and Aeroengine Congress and Exhibition, Atlanta, GA, June 16–19, 2003. Manuscript received by the IGTI December 2002; final revision March 2003. Paper No. 2003-GT-38304. Review Chair: H. R. Simmons.
Stieger, R. D., and Hodson, H. P. (December 29, 2004). "The Transition Mechanism of Highly Loaded Low-Pressure Turbine Blades ." ASME. J. Turbomach. October 2004; 126(4): 536–543. https://doi.org/10.1115/1.1773850
Download citation file: