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-   -   Poor Residuals at Intersection Between Symmetry Plane and Airfoil Leading Edge (http://www.cfd-online.com/Forums/cfx/72585-poor-residuals-intersection-between-symmetry-plane-airfoil-leading-edge.html)

TWaung February 10, 2010 17:26

Poor Residuals at Intersection Between Symmetry Plane and Airfoil Leading Edge
 
Hi,

I am modeling a geometry where I have half a symmetrical airfoil section lying along a symmetry plane (the symmetry plane basically cuts the airfoil profile in half).

I am finding regions of high residuals located right along the leading edge of the airfoil for the momentum residuals in the direction perpendicular to the symmetry plane. The airfoil profile has a relatively sharp leading edge.

Does using a symmetry plane to cut an airfoil profile in half cause these poor residuals? I have tried refining the grid around the leading edge but have been unable to completely remove the regions of poor residuals.

The flow direction is always parallel to the airfoil chord, and the airfoil section is attached to another body.

I am using the High Resolution scheme, the SST turbulence model, running steady state, and local timescale factor of 5.

Thanks

Tim

ghorrocks February 10, 2010 17:46

Could it be a small separation or flow instability? This can show up as a region of high residuals.

feizaghaee February 16, 2010 09:11

have you tried lower time scale? in steady state it's used for relaxing the equations. sometimes it works.


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