buoyantFoam水库计算
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请问大家有用buoyantPimpleFoam算过Johnson水库水温动力学算例吗？这个水库的工况是：初始充满21.44°C的水，在入口处以固定速度0.014m/s进16.67°C的冷水，出水口自由出流。模拟近28万个网格。
x-y平面：
x-z平面：
顶面为自由液面，设置成滑移边界条件，采用buoyantkEpsilon模型，但是计算出来一开始感觉流速场就不合理了（图为水平流速和总流速）。
条件设置如下，请问哪里有问题？object U; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 1 -1 0 0 0 0]; internalField uniform (0 0 0); boundaryField { inlet { type fixedValue; value uniform (0.014 0 0); } outlet { type slip; } walls { type fixedValue; value uniform (0 0 0); } outletwater { type inletOutlet; inletValue uniform (0 0 0); value $internalField; } } // ************************************************************************* // object p_rgh; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [1 -1 -2 0 0 0 0]; internalField uniform 1e5; boundaryField { walls { type fixedFluxPressure; value uniform 1e5; } inlet { type fixedFluxPressure; value uniform 1e5; } outletwater { type fixedFluxPressure; value uniform 1e5; } outlet { type prghPressure; p uniform 1e5; value uniform 1e5; } } // ************************************************************************* // object T; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 0 0 1 0 0 0]; internalField uniform 294.59; boundaryField { walls { type zeroGradient; } inlet { type fixedValue; value uniform 289.82; } outlet { type inletOutlet; inletValue $internalField; value $internalField; } outletwater { type inletOutlet; inletValue $internalField; value $internalField; } } // ************************************************************************* // object k; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 2 -2 0 0 0 0]; internalField uniform 1e-5; boundaryField { walls { type kqRWallFunction; value $internalField; } inlet { type fixedValue; value $internalField; } outlet { type inletOutlet; inletValue $internalField; value $internalField; } outletwater { type inletOutlet; inletValue $internalField; value $internalField; } } // ************************************************************************* // object fvSolution; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // solvers { "rho.*" { solver PCG; preconditioner DIC; tolerance 0; relTol 0; } p_rgh { solver PCG; preconditioner DIC; tolerance 1e-8; relTol 0.01; } p_rghFinal { $p_rgh; relTol 0; } "(U|h|e|k|epsilon|R)" { solver PBiCGStab; preconditioner DILU; tolerance 1e-6; relTol 0.1; } "(U|h|e|k|epsilon|R)Final" { $U; relTol 0; } } PIMPLE { momentumPredictor yes; nOuterCorrectors 2; nCorrectors 3; nNonOrthogonalCorrectors 0; } // ************************************************************************* // object fvSchemes; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // ddtSchemes { default Euler; } gradSchemes { default Gauss linear; } divSchemes { default none; div(phi,U) Gauss upwind; div(phi,h) Gauss upwind; div(phi,e) Gauss upwind; div(phi,k) Gauss upwind; div(phi,epsilon) Gauss upwind; div(phi,R) Gauss upwind; div(phi,K) Gauss linear; div(phi,Ekp) Gauss linear; div(R) Gauss linear; div(((rho*nuEff)*dev2(T(grad(U))))) Gauss linear; div(phiv,p) Gauss upwind; } laplacianSchemes { default Gauss linear corrected; } interpolationSchemes { default linear; } snGradSchemes { default corrected; } // ************************************************************************* // -
@cfd20
我看到一个比较关键的地方：我觉得，墙函数是非常关键的边界条件。 特别是在 RANS 中。
我看到你对 alphat， epsilon 都用了墙函数，速度为什么不用，没有理由？
有确定边界层节点足够覆盖边界层了么？
我这有个参考资料：
ansys 17 手册:
The thickness of the prism
layer should be designed to ensure that around 15 or more nodes are actually covering the boundary
layer. This can be checked after a solution is obtained, by looking at the turbulent viscosity, which has
a maximum in the middle of the boundary layer – this maximum gives an indication of the thickness
of the boundary layer -
（计算11min后在x=11.43m处中垂线水平流速分布图）