Available turbulence models predict much shorter regions of transition than indicated by the heat transfer co-efficient data on turbine airfoil suction surfaces. Analysis of recently acquired data, for simulated suction surfaces of turbine airfoils, indicates that the extent of transition region deduced from heat transfer co-efficient distribution can be different from the one deduced from momentum boundary layer parameters. In accelerating flows the extent of transition indicated by heat transfer data is larger than the one indicated by the momentum boundary layer parameters, the opposite is true for boundary layers developing under the effect of adverse pressure gradients. A simple model, proposed to account for the effect of free stream pressure gradient on the extent of transition in boundary layers, is shown to yield good estimate of both heat transfer co-efficient and aerodynamic losses on turbine airfoil suction surfaces.
Momentum and thermal boundary layers on turbine airfoil suction surfaces
Momenten- und thermische Grenzschichten auf den Saugflaechen von Turbinenschaufeln
AIAA-Papers ; Jul ; 1-10
1987
10 Seiten, 7 Bilder, 40 Quellen
Conference paper
English