各位大佬好!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:
湍流模型为 RAS kOmegaSST,边界条件参考Chalmers大学教程设置:
计算结果如下:最大库朗数<0.3,最大壁面y+<0.1,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。
fvSolution:
solvers
{
p
{
solver PCG;
preconditioner DIC;
tolerance 1e-05;
relTol 0.01;
}
pFinal
{
solver PCG;
preconditioner DIC;
tolerance 1e-07;
relTol 0;
}
U
{
solver BiCGStab;
preconditioner DILU;
tolerance 1e-08;
relTol 0;
}
k
{
solver BiCGStab;
preconditioner DILU;
tolerance 1e-08;
relTol 0;
}
omega
{
solver BiCGStab;
preconditioner DILU;
tolerance 1e-08;
relTol 0;
}
}
PISO
{
momentumPredictor yes;
nCorrectors 3;
nNonOrthogonalCorrectors 2;
pRefCell 0;
pRefValue 0;
}
fvSchemes:
ddtSchemes
{
default CrankNicolson 0.7;
}
gradSchemes
{
// default cellLimited Gauss linear 0;
// grad(U) cellLimited Gauss linear 0.333;
default leastSquares;
}
divSchemes
{
default none;
div(phi,U) Gauss linearUpwind 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;
}
跪求大佬指点迷津,如何提高St计算精度。