Heat Transfer on Three Turbine Airfoils.
Abstract
An experimental heat transfer program and a smoke visualization study were conducted on three turbine airfoils in a stationary cascade tunnel. The three blades with different profile shapes were scaled to have a same chord length of 21 inches; all blade models had a turning angle of 72 degrees. The ranges of the test parameters were for the Reynolds number, from 7.8 x 10 to the 5th power to 1.5 x 10 to the 6th power; and for main stream turbulence intensity, from 0.8 to 8.0 percent. On a blade with severe pressure-side curvature where a previous investigation had revealed intermittent bursts of Gortler vortices, the measured heat transfer rates were 20 to 50 percent higher than those on the blade with least pressure-side curvature where the flow was mostly laminar. Evidence of the heat transfer distributions strongly indicates transition to turbulent boundary layers with Gortler vortices as a catalyst. Chordwise heat transfer fluctuations or waviness, which were also observed in other investigations, were found to exist in cases where Gortler vortices made their presence. In regions of strong streamwise acceleration, upstream turbulence intensity and Gortler vortices became less potent in raising the heat transfer rates. In the leading edge region, data from this study agreed well with the empirical correlations between the local curvature Reynolds number and the freestream turbulence intensity.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1983
- Accession Number
- ADA128762
Entities
People
- Arnon Chait
- John R. Rapp
- Lit. S. Han
- William F. Boyee
Organizations
- Ohio State University