lift and drag coefficient of box
Hello!
I visualized turbulent flow around a box. I try to calculate lift and drag coefficients. In controlDict I add functions { forces { type forceCoeffs; functionObjectLibs ( "libforces.so" ); outputControl timeStep; outputInterval 1; patches ( box ); rhoName rhoInf; log true; rhoInf 1.2041; CofR ( 0 0 0 ); liftDir (0 1 0); dragDir (0 0 1); pitchAxis (0 0 0); magUInf 4.0; lRef 0.8; Aref 0.64; } } At the end of time, I have a file forces. The results are wrong: Cd=1.85 Cl=12665 Size of box: fin is 0.8m Size of tunnel: fin is 5.6m, heigh is 2.4m Where I have a mistake? 
Nobody has problems with problem like this?..

hi akuji,
if your simulation is 2D, then you have to check your Aref. lets say your 2D mesh is only 1 mm thick than you have to set your Aref Aref=lRef*thicknessofmesh=0.8/0.001 Edit: Sorry, it should be Aref=0.8*0.001 not 0.8/0.001 
Quote:
And...if my mesh is 3D? (It's really 3d) 
in openfoam it is always 3D. with 2D i meant that front and back patches are empty. the 3rd dimension is the thickness of the volume.
best regards 
Well, I find a right solution. But I still have a question.
rhoName rhoInf; log true; rhoInf 1.2041; CofR ( 0 0 0 ); liftDir (0 0.01 0); dragDir (0 0 1); pitchAxis (0 0 0); magUInf 4.0; lRef 0.8; Aref 0.64; Why I need to set liftDir 0.01? 
And one more question:)
I find information, that wrong to calculate lift coefficient if square of windward surface is not equal of square of downwind surface. What to do in this case? 
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