[bullmut]

Hi there, i have been trying to model a sg6041 foil in openfoam.
Its a simple mesh done through snappyhexmesh with the foil inputed as a stl. I have split the foil into 4 sections and included a refinement box around the foil.
My question is about the lift and drag...
When i run simpleFoam for my case i get a CL = 0.1402 and a CD of 0.00646, which is to far off when compared to the same foil run through the xfoil program - xfoil reported CL = 0.287 and CD = 0.00407.

I am using the KSST model with initial K = 1.19 and omega = 17.94
I run the simulation for 4000 iterations, and the last run of my log file is below

Case info:
Frestream velocity = 26.75m/s
Re = 1779735 equates to kinematic viscosity = 1.5e-5
Chord of 1m
Depth of 0.1m
The top and bottom patches are set to symmetry

I have attached 2 images of my mesh, i will send the polymesh to anyone but i have no site to post it on and its too big for the forum...
I have also attached my initial conditions and the forces file i use to calc CL and CD
forcesDn are the lower half of the foil and forcesUp are the upper half. Finally forces T looks athe entire foil as does the coeff section. The split was a check on patch referencing i was doing.
I cant figure out why the large difference in my coefficients.
I am struggling with what seems to be a small issue for a while now and i think i am losing it..
Please any help is appreciated.
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Time = 4000

smoothSolver: Solving for Ux, Initial residual = 1.02476e-08, Final residual = 7.66026e-10, No Iterations 1
smoothSolver: Solving for Uy, Initial residual = 9.04285e-09, Final residual = 9.04285e-09, No Iterations 0
GAMG: Solving for p, Initial residual = 1.49412e-07, Final residual = 8.26346e-09, No Iterations 1
time step continuity errors : sum local = 3.7976e-10, global = 2.87202e-12, cumulative = 0.000439424
smoothSolver: Solving for omega, Initial residual = 9.88073e-09, Final residual = 9.88073e-09, No Iterations 0
smoothSolver: Solving for k, Initial residual = 9.84067e-09, Final residual = 9.84067e-09, No Iterations 0
ExecutionTime = 66.76 s ClockTime = 67 s

forces forcesUp output:
sum of forces:
pressure : (0.0762727 5.43847 -9.67512e-19)
viscous : (0.0736868 0.00385495 1.43458e-20)
porous : (0 0 0)
sum of moments:
pressure : (-0.679809 0.00953408 0.76145)
viscous : (-0.000481869 0.00921084 -0.00687399)
porous : (0 0 0)

forces forcesDn output:
sum of forces:
pressure : (0.0213602 -0.424607 2.4701e-19)
viscous : (0.0598335 -0.00170402 -4.72061e-21)
porous : (0 0 0)
sum of moments:
pressure : (0.0530759 0.00267002 0.345743)
viscous : (0.000213003 0.00747919 0.00256536)
porous : (0 0 0)

forces forcesT output:
sum of forces:
pressure : (0.0976329 5.01386 -7.20502e-19)
viscous : (0.13352 0.00215093 9.62519e-21)
porous : (0 0 0)
sum of moments:
pressure : (-0.626733 0.0122041 1.10719)
viscous : (-0.000268866 0.01669 -0.00430862)
porous : (0 0 0)

forceCoeffs forceCoeffs output:
Cm = 0.000807592
Cd = 0.00646074
Cl = 0.140198
Cl(f) = 0.0709065
Cl(r) = 0.0692913

End
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