@random_ran 老师您好!借楼向您请教一些问题。我目前进行二维圆柱绕流的计算,Re=1e4和5e4。圆柱直径D=0.1m,介质是水(nu=1e-6),计算域和生成网格(STARCCM生成并导入)如图所示:
图片1.png
图片3.png
湍流模型为 RAS kOmegaSST,边界条件参考Chalmers大学教程设置:
图片2.png
计算结果如下:最大库朗数为0.27,最大壁面y+<0.3,阻力系数误差<1%,St误差约为30%。St计算公式为:fD/U,f由升力时历曲线fft得到。
fvSchemes:
ddtSchemes
{
default Euler;
}
gradSchemes
{
default cellLimited Gauss linear 0.5;
//grad(p) Gauss linear;
grad(U) cellLimited Gauss linear 1;
}
divSchemes
{
default none;
div(phi,U) Gauss linearUpwindV grad(U);
div(phi,k) Gauss linearUpwind default;
div(phi,omega) Gauss linearUpwind default;
div((nuEff*dev(T(grad(U))))) Gauss linear;
}
laplacianSchemes
{
default Gauss linear limited 1;
}
interpolationSchemes
{
default linear;
}
snGradSchemes
{
default limited 1;
}
fvSolution
solvers
{
p
{
solver PCG;
preconditioner DIC;
tolerance 1e-08;
relTol 0;
}
pFinal
{
solver PCG;
preconditioner DIC;
tolerance 1e-08;
relTol 0;
}
U
{
solver BiCGStab;
preconditioner DILU;
tolerance 1e-07;
relTol 0;
}
k
{
solver BiCGStab;
preconditioner DILU;
tolerance 1e-07;
relTol 0;
}
epsilon
{
solver BiCGStab;
preconditioner DILU;
tolerance 1e-07;
relTol 0;
}
omega
{
solver BiCGStab;
preconditioner DILU;
tolerance 1e-07;
relTol 0;
}
}
PISO
{
nCorrectors 3;
nNonOrthogonalCorrectors 3;
pRefCell 0;
pRefValue 0;
}
跪求老师指点迷津,如何提高St计算精度。