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Problem with Lift and Drag coeffs

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Old   August 7, 2018, 13:52
Question Problem with Lift and Drag coeffs
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alfonsofsm is on a distinguished road
Hello, everyone

Is my first time asking here. I have searched an answer for my questions in every previous thread but I could not find it, so here I go:

Im simulating an USV (Unmanned Surface Vessel), multiphase, with interFoam. My intention is to obtain Lift and Drag coefficients, but, I do not know why, I keep getting ridiculous numbers:

Cm = -1.22607e-299
Cd = 5.39348e-300
Cl = 8.5342e-300
Cl(f) = -7.99359e-300
Cl(r) = 1.65278e-299

I am also calculation forces, and they seem pretty correct, at least their magnitude does
(-5.713676e+01 6.513626e+02 1.482553e+03)

I have checked my Aref (frontal Area in m2), lRef (hull length), magUinf (free stream velocity), rhoInf...
type forceCoeffs;
functionObjectLibs ( "" );
outputControl timeStep;
outputInterval 1;
patches (hull);

pName p;
UName U;
log true;
rhoInf 1025;

CofR (1.067 0 0.0725)
liftDir (0 0 1);
dragDir (-1 0 0);
pitchAxis (0 1 0);
magUInf 3.0684;
lRef 2.27;
Aref 0.05;

Does anyone know what could be making me get so low coeffs? Is there any other parameter affecting? I have also tried modifying the mesh, timeStep...

Thank you very much in advance
alfonsofsm is offline   Reply With Quote


coefficients, drag, hull, interfoam, lif

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