The UMIST-N Near-Wall Treatment Applied to Periodic Channel Flow
The UMIST-N Near-Wall Treatment Applied to Periodic Channel Flow
The UMIST-N Near-Wall Treatment Applied to Periodic Channel Flow
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Chapter 2<br />
Turbulence Models<br />
<strong>The</strong> Reynolds Averaged Navier S<strong>to</strong>kes equations are obtained for continuity,<br />
conservation of momentum, and generic transport. <strong>The</strong> assumptions of the<br />
EVM are employed where appropriate. <strong>The</strong>n, specific transport equations<br />
are introduced for the turbulence parameters tracked by the k-ε and k-ω<br />
models. <strong>The</strong> logarithmic law of the wall is introduced.<br />
2.1 Reynolds Averaging<br />
Consider a flow field containing an incompressible fluid with constant proper-<br />
ties: density (ρ), dynamic viscosity (µ), and kinematic viscosity (ν = µ<br />
). In ρ<br />
Cartesian coordinates, the flow field extends in three orthogonal directions,<br />
x, y, and z. <strong>The</strong> flow field may vary in time, t. A pressure field, P (x, y, z, t)<br />
and a velocity field, U (x, y, z, t) = (U, V, W ) T are associated with the flow.<br />
This flow field is governed by continuity and the conservation of momentum.<br />
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