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-   -   Mesh geometry over airfoil with Gambit (http://www.cfd-online.com/Forums/fluent/42665-mesh-geometry-over-airfoil-gambit.html)

 laith October 23, 2006 17:56

Mesh geometry over airfoil with Gambit

Hi friends to Create grid generation the Geometry of domain in GAMBIT over airfoil used W=12.5*c and L=20*c Notes that the below paragraph is form Fluent Tutorial /Flow over an airfoil (In an external flow such as that over an airfoil, we have to define a farfield boundary and mesh the region between the airfoil geometry and the farfield boundary. It is a good idea to place the farfield boundary well away from the airfoil since we'll use the ambient conditions to define the boundary conditions at the farfield. The farther we are from the airfoil, the less effect it has on the flow and so more accurate is the farfield boundary condition).

My question is, the effect of geometry domain on Far-field boundary! Strem function(Far)=U*Y-V*X vortisity(far)=0 I mean if i used smaller dimention of geometry like is W=5*c and L=5*c what happen

Thanks laith Laith20042001@yahoo.com

 M. essuri October 26, 2006 12:20

Re: Mesh geometry over airfoil with Gambit

hi you should make the so called grid indpendance study. Try decrasing domain size change, and mesh number. You will probablly find good solutions for low angles of attack, but not good for heigher onces.

I tryied by largest angle of attack for every velocity, trid to change domain size, when the disturbances caused by the airfoil does not propagate to the boundaries then I accept this size. No more.

 matty October 26, 2006 19:36

Re: Mesh geometry over airfoil with Gambit

you might end up with inaccurate results due to blockage effects.