A lag model for turbulent boundary layers developing over rough bleed surfacesBoundary layer mass removal (bleed) through spanwise bands of holes on a surface is used to prevent or control separation and to stabilize the normal shock in supersonic inlets. The addition of a transport equation lag relationship for eddy viscosity to the rough wall algebraic turbulence model of Cebeci and Chang was found to improve agreement between predicted and measured mean velocity distributions downstream of a bleed band. The model was demonstrated for a range of bleed configurations, bleed rates, and local free stream Mach numbers. In addition, the model was applied to the boundary layer development over acoustic lining materials for the inlets and nozzles of commercial aircraft. The model was found to yield accurate results for integral boundary layer properties unless there was a strong adverse pressure gradient.
Document ID
19930064184
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Lee, J. (NASA Lewis Research Center Cleveland, OH, United States)
Sloan, M. L. (NASA Lewis Research Center Cleveland, OH, United States)
Paynter, G. C. (Boeing Commercial Airplane Group Seattle, WA, United States)