
Accession Number : ADA132906
Title : Nonuniqueness in Wakes and Boundary Layers,
Corporate Author : UNITED TECHNOLOGIES RESEARCH CENTER EAST HARTFORD CT
Personal Author(s) : Smith,F T
PDF Url : ADA132906
Report Date : May 1983
Pagination or Media Count : 52
Abstract : In streamlined flow past a flat plate aligned with a uniform stream, it is shown that (a) the Goldstein nearwake and (b) the Blasius boundary layer are nonunique solutions locally for the classical boundary layer equations, whereas (c) the RottHakkinen verynearwake appears to be unique. In each of (a), (b) an alternative solution exists which has reversed flow and which apparently cannot be discounted on immediate grounds. Thus, depending mainly on how the alternatives for (a), (b) develop downstream, the symmetric flow at high Reynolds numbers could have 2, 4 or more, simple steady forms. Concerning nonstreamlined flow, e.g. past a bluff obstacle, new similarity forms are described for the pressurefree viscous symmetric closure of a predominantly slender long wake beyond a largescale separation. Features arising include nonuniqueness, singularities and algebraic behavior, consistent with nonentraining shear layers with algebraic decay. Nonuniqueness also seems possible in reattachment onto a solid surface and for nonsymmetric or pressurecontrolled flows including the wake of a symmetric cascade.
Descriptors : *Boundary layer flow, *Wake, Flat plate models, Equations of motion, Partial differential equations, Reynolds number, Downstream flow
Subject Categories : Numerical Mathematics
Fluid Mechanics
Distribution Statement : APPROVED FOR PUBLIC RELEASE