Mean flow in turbulent boundary layers disturbed to alter skin frictionA comparative evaluation is made of recent developments in methods for the reduction of boundary layer drag, encompassing longitudinal surface riblets, 'outer layer' devices, (OLDs) and longitudinal convex surface curvature. The boundary layer of a surface with a longitudinal concave curvature is also studied, to complement the convex case results. The net drag reductions achievable by both riblets and OLDs are noted to be a rather modest 10 percent. Boundary layers exhibit asymmetric response to streamwise surface curvatures, with the response being slower for the case of a concave than a convex curvature.
Document ID
19860053744
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Bandyopadhyay, P. R. (NASA Langley Research Center Hampton, VA, United States)