Hostname: page-component-8448b6f56d-m8qmq Total loading time: 0 Render date: 2024-04-19T15:58:35.812Z Has data issue: false hasContentIssue false

On the calculation of separation bubbles

Published online by Cambridge University Press:  20 April 2006

Tuncer Cebeci
Affiliation:
Mechanical Engineering Department, California State University, Long Beach
Keith Stewartson
Affiliation:
Department of Mathematics, University College London

Abstract

The interactive boundary-layer equations for a flat plate are solved numerically when the external velocity field is piecewise linear and would provoke separation if the response of the boundary layer were neglected. A comparable problem had already been solved by Briley using the full Navier–Stokes equations. The equations are solved for various values of the Reynolds number and x0, a parameter defining the corner point of the external velocity. It is found that flows with a limited region of separation can be computed, but that, if x0 is too large, the numerical procedure breaks down. Furthermore, this maximum value is a decreasing function of R and seems to approach the value 0.12 predicted by classical theory as R → ∞. Comparison with Briley's results indicate a reasonable agreement except that different values of x0 are appropriate. It is conjectured that, once x0 increases above the acceptable maximum, rapid changes occur in the flow properties when R is large.

Type
Research Article
Copyright
© 1983 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Briley, W. R. 1971 A numerical study of laminar separation bubbles using the Navier-Stokes equations J. Fluid Mech. 47, 713736.Google Scholar
Carter, J. E. 1975 Inverse solutions for laminar boundary-layer flows with separation and reattachment. NASA Tech. Rep. TR R-447.Google Scholar
Cebeci, T. 1983 A time-dependent approach for calculating steady inverse boundary-layer flows with separation. Proc. R. Soc. Lond. (to be published).Google Scholar
Cebeci, T., Keller, H. B. & Williams, P. G. 1979 Separating boundary-layer flow calculations J. Comp. Phys. 31, 363378.Google Scholar
Cebeci, T., Stewartson, K. & Williams, P. G. 1980 Separation and reattachment near the leading edge of a thin airfoil at incidence. Computation of viscous-inviscid interactions. Agard Conf. Proc. no. 291, Colorado Springs.Google Scholar
Dijkstra, K. 1978 Separating incompressible laminar boundary-layer flow over a smooth step of small height. In Proc. 6th Intl Conf. Numerical Methods in Fluid Dynamics. Tbilisi, USSR, pp. 4552.Google Scholar
Goldstein, S. 1948 On laminar boundary-layer flow near a point of separation Q. J. Mech. Appl. Maths 1, 4369.Google Scholar
Howarth, L. 1938 On the solution of the laminar boundary-layer equation Proc. R. Soc. Lond. A164, 547.Google Scholar
Reyhner, T. A. & FLUGGE-LOTZ, I. 1968 The interaction of a shock wave with a laminar boundary layer Intl. J. Nonlinear Mech. 3, 173199.Google Scholar
Smith, F. T. 1979 Laminar flow of an incompressible fluid past a bluff body, the separation, reattachment, eddy properties and drag J. Fluid Mech. 92, 171205.Google Scholar
Smith, F. T. 1982 Theory of laminar streaming flows IMA J. Mech. 28, 207281.Google Scholar
Stewartson, K. 1970 Is the singularity at separation removable? J. Fluid Mech. 44, 347364.Google Scholar
Stewartson, K. 1982 D'Alembert's Paradox SIAM Rev. 23, 308343.Google Scholar
Stewartson, K., Smith, F. T. & Kaups, K. 1982 On marginal separation Stud. Appl. Maths 67, 4561.Google Scholar
Veldman, A. E. P. 1979 A numerical method for the calculation of laminar incompressible boundary layers with strong-inviscid interaction. NLR TR 79023L.Google Scholar
Williams, P. G. 1975 A reverse flow computation in the theory of self-induced separation. In Proc. 4th Intl Conf. on Numerical Methods in Fluid Dynamics (ed. R. D. Richtmyer). Lecture notes in physics, vol. 35, pp. 445451.