47 lines
1 KiB
C
47 lines
1 KiB
C
if(sigmaExpMethod == "standard")
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{
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sigmaExp = fvc::div
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(
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mu*gradU.T() + lambda*(I*tr(gradU)) - (mu + lambda)*gradU,
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"div(sigma)"
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);
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}
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else if(sigmaExpMethod == "surface")
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{
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sigmaExp = fvc::div
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(
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muf*(mesh.Sf() & fvc::interpolate(gradU.T()))
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+ lambdaf*(mesh.Sf() & I*fvc::interpolate(tr(gradU)))
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- (muf + lambdaf)*(mesh.Sf() & fvc::interpolate(gradU))
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);
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}
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else if(sigmaExpMethod == "decompose")
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{
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surfaceTensorField shearGradU =
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((I - n*n)&fvc::interpolate(gradU));
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sigmaExp = fvc::div
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(
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mesh.magSf()
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*(
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- (muf + lambdaf)*(fvc::snGrad(U)&(I - n*n))
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+ lambdaf*tr(shearGradU&(I - n*n))*n
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+ muf*(shearGradU&n)
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)
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);
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}
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else if(sigmaExpMethod == "expLaplacian")
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{
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sigmaExp =
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- fvc::laplacian(mu + lambda, U, "laplacian(DU,U)")
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+ fvc::div
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(
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mu*gradU.T()
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+ lambda*(I*tr(gradU)),
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"div(sigma)"
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);
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}
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else
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{
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FatalError << "sigmaExp method " << sigmaExpMethod << " not found!" << endl;
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}
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