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how to discretize fourth order term

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Old   August 1, 2011, 18:27
Default [solved]how to discretize fourth order term
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Mieszko Młody
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Dear Foamers,
Does anyone of you know what is the best way to make 4 order term discretization:
I mean:
U(x,y)
U_xxxx + U_yyyy

Thanks
ZM

Last edited by ziemowitzima; August 4, 2011 at 12:27. Reason: solved
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Old   August 2, 2011, 17:54
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so far I found such explicit solution (U == T):

volVectorField gradT=fvc::grad(T); // (T_x, T_y)
volScalarField Txxxx = gradT.component(0); // T_x
gradT = fvc::grad(Txxxx); // (T_xx, T_xy)
Txxxx = gradT.component(0); // T_xx
gradT = fvc::grad(Txxxx); // (T_xxx, T_xxy)
Txxxx = gradT.component(0); // T_xxx
gradT = fvc::grad(Txxxx); // (T_xxxx, T_xxxy)
Txxxx = gradT.component(0); // T_xxxx

Maybe someone have some better idea ?
Is it possible to descritize T_xxxx implicitly ?

-ZM
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Old   August 4, 2011, 12:26
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seems to be solved:
differentiation in one direction
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