Turbulent Transport Measurements in a Heated Boundary Layer: Combined Effects of Free-Stream Turbulence and Removal of Concave Curvature

摘要: Turbulence measurements for both momentum and heat transport are taken in a boundary layer over flat recovery wall downstream of concave (R = 0.97 m). The appears turbulent from the beginning upstream, grows test curved with negligible streamwise acceleration. strength curvature at bend exit, δ99.5 /R , is 0.04. free-stream turbulence intensity (FSTI) ~8 percent curve nearly uniform ~4.5 throughout wall. Comparisons made data an earlier study, same facility, but low FSTI (~0.6 percent). Results show that on wall, elevated enhances quantities such as −uν νt most outer part layer, near-wall values remain unaffected. This contrast to within which decrease when increased. At decreases due removal become more profound elevated, compared low-FSTI behavior. Measurements core flow indicate high levels cross upstream cease removed. Other results Prandtl numbers reduced ~0.9 consistent rise Stanton