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First cell height calculation

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* [[Dimensionless wall distance (y plus)]]
* [[Dimensionless wall distance (y plus)]]
* [ recover deleted files]
* [[Friction velocity]]
* [[Friction velocity]]
* [[Wall shear stress]]
* [[Wall shear stress]]

Latest revision as of 05:06, 29 November 2011

Mesh classification
Structured mesh generation
Unstructured mesh generation
Special topics

While performing CFD simulations, it is critical that one capture boundary layer near the wall properly. In order to do that, the mesh should be generated in such a manner that it captures boundary layer properly. For turbulent flows, calculation of the Y plus value of the first interior node/gridpoint helps in doing that. This dimensionless distance is defined as

y^+ := \frac{u_* \, y}{\nu}

where u_* is the friction velocity defined as

u_* := \sqrt{\frac{\tau_w}{\rho}}.

The wall shear \tau_w can probably not be determined until after a simulation has been completed, so it is usually necessary to estimate a value, and then check after a simulation is complete.

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