A Note on Kinetic Energy, Dissipation and Enstrophy
نویسندگان
چکیده
The dissipation rate of a Ncwtonian fluid with constant shear viscosity can be shown to include three constituents: dilatation, vorticity, and surface strain. The last one is found to make no contributions to the change of kinetic energy. These dissipation constituents are used to identify typical compact turbulent flow structures at high Reynolds numbers. The incompressible version of the simplified kinetic-energy equation is then cast to a novel form, which is free from the work rate done by surface stresses but in which the full dissipation reenters. Key words, kinetic energy, dissipation, enstrophy, surface strain Subject classification. Fluid Mechanics
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