Intense Viscous Dissipation Events and the Vorticity Field in Near-Wall Turbulence
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In high Reynolds number turbulent flows there exists a close statistical relationship between the mean viscous dissipation rate e and the mean enstrophy field (Tennekes & Lumley, 1972). For near-wall shear-driven turbulent flows the intensities of the turbulent velocity and vorticity fields attain their maxima close to the boundary in an area of high viscous dissipation. This suggests that the processes underlying turbulent energy, enstrophy and dissipation generation may be (and are) related, but the constraints imposed by the wall leads to the expectation that the same flow structures may be involved in all three processes. Conditional sampling of the turbulent flow field around ejection and sweep events shows that most of the dissipation and enstrophy generation occurs near the energy producing events — with some of these events involving greater dissipation than production of turbulent energy (Gavrilakis, 1996). The present report looks at the relation between the generation of the turbulent energy dissipation and enstrophy fields in the vicinity of a smooth wall.
KeywordsDirect Numerical Simulation Viscous Sublayer Spectral Element Method Rectangular Duct Streamwise Vorticity
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- Gavrilakis, S., 1996: Dissipative flow structures within near-wall turbulence-producing events. Advances in Turbulence VI, Gavrilakis, Machiels & Monke-witz (Eds.), Kluwer Academic.Google Scholar
- Gavrilakis, S., L. Machiels, & M. O. Deville, 1996: A spectral element method for direct simulation of turbulent flows with two inhomogeneous directions. Proceeding of the ECCOMAS 96 Conference, Paris, September 9–13.Google Scholar
- Gilbert, N., 1993: Turbulence model data derived from direct numerical simulations. DLR Internal Report IB 221-93 A 14.Google Scholar
- Gilbert, N., & L. Kleiser, 1991: Turbulence model testing with the aid of direct numerical simulation results. Proc. of 8th Symposium on Turbulent Shear Flows, Paper 26-1, Munich, Sept. 9–11.Google Scholar
- Maday, Y., & A. T. Patera, 1989: Spectral element methods for the Navier-Stokes equations. State-of-the art surveys in computational mechanics, ASME p. 71, A.K. Noor and J.T. Oden, Editors, New York.Google Scholar
- Rønquist, E. M., 1991: Spectral element methods for the unsteady Navier-Stokes equations. Von Karman Institute Lecture Series.Google Scholar
- Tennekes, H. & J. L. Lumley, 1972: A First Course in Turbulence, MIT Press.Google Scholar