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Eddy Viscosity and Entrainment in Equilibrium Boundary Layers

Published online by Cambridge University Press:  07 June 2016

M R Head
Affiliation:
Cambridge University, Engineering Department
R A McD Galbraith
Affiliation:
Cambridge University, Engineering Department
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Summary

The properties of equilibrium turbulent boundary layers have been examined using Thompson’s family of velocity profiles along with alternative π – G relationships. The relationship which is in best agreement with measurements of equilibrium layers confirms an earlier suggestion that (νT/Uδ*)max is not a universal constant for such layers but decreases for small and negative values of π. A close relationship is established between eddy viscosity and entrainment, and it is shown that veδ/νT is effectively constant for π > 2.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society. 1975

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References

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