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The flow at a rear stagnation point is eventually determined by exponentially small values of the velocity

Published online by Cambridge University Press:  20 April 2006

Leon L. van Dommelen
Affiliation:
FAMU/FSU College of Engineering, Tallahassee, FL, USA
Shan Fu Shen
Affiliation:
Cornell University, Ithaca, NY, USA

Abstract

It is suggested that current conceptions about unsteady rear-stagnation-point flow do not fully describe the physics, since they show discrepancies from recent numerical results. The previously neglected exponentially small rotational perturbation velocity above the boundary-layer proves to have a dominating influence on the final boundary-layer development. An asymptotic analysis reveals possible difficulties for common computational schemes for viscous flows. Failure of the usual asymptotic matching rule in the analysis is in accordance with Fraenkel's warning on logarithmic expansions.

Type
Research Article
Copyright
© 1985 Cambridge University Press

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