CFD中文网

wsy11

@pikaa 这个应该不需要严格对应，目前我的设置是尽量使stl的长宽稍大于blockmesh的大小

wsy11

@pikaa 感谢您的回答，这个参数设置了，之间检查过，应该是正确的

wsy11

@刚开始学流体力学
我看了您之前的帖子，咱们是一个方向的，我也是在处理wrf+CFD的问题

wsy11

@刚开始学流体力学
我也是把网格量减少了，可以成功运行一段时间，但是运行一段时间后还是发散，请问您是多大的地形，以及运行多长的模拟？

wsy11

如题，在我使用snappyhexmesh生成复杂地形网格时，当网格点很多时，会出现两个底面，也就是blockmesh中的面无法被地形面替换，尝试修改了最大网格数这个参数，但是没有效果。
如果有研究过地形网格问题的老师，能不能帮忙看下应该修改什么参数？
如图，存在两个底面：

理想情况下，应该如下图所示：

以下是我的snappyhexmesh：
snappyHexMeshDict
以及blockMesh：blockMeshDict

wsy11

找到问题所在了：是划分网格时出现的问题，但是仍然解决不了
如图：blockMeshDict设置相同范围（3000m3000m600m时），但是网格大小不同时（网格大小图一：100m，图二：60m），网格变小会导致划分失败（如图，地面仍然为平面，而不是stl文件）
图一：

图二：底面变成真实地形

wsy11

如题，我使用相同snappyhexmesh文件来对blocckmesh网格和地形stl文件进行划分，当范围选择为2000m*2000m*630m时（case1），可以进行正常的网格划分和运算；当范围增大到3000m*3000m*630m时（case2），无法进行正常运算，case2会发散。
（具体算例文件：wcase.zip ，stl文件文件过大无法上传）
（只修改了xmin,xmax,ymin,ymax,并且网格大小也一致，而且两个case划分好网格以后checkMesh都没问题）。

运行结果如下：
case1正常运行
case2发散：

Time = 178s

smoothSolver:  Solving for Ux, Initial residual = 0.446597, Final residual = 0.0256856, No Iterations 3
smoothSolver:  Solving for Uy, Initial residual = 0.422256, Final residual = 0.0231428, No Iterations 3
smoothSolver:  Solving for Uz, Initial residual = 0.497265, Final residual = 0.0275248, No Iterations 3
GAMG:  Solving for p, Initial residual = 0.0065485, Final residual = 0.000418695, No Iterations 4
time step continuity errors : sum local = 1.68504e+18, global = 1.42803e+16, cumulative = 9.69486e+16
ExecutionTime = 15.72 s  ClockTime = 18 s

Time = 179s

[38] #0  Foam::error::printStack(Foam::Ostream&) at ??:?
[38] #1  Foam::sigFpe::sigHandler(int) at ??:?
[38] #2  ? in "/lib64/libc.so.6"
[38] #3  Foam::pow3(Foam::Field<double>&, Foam::UList<double> const&) at ??:?
[38] #4  void Foam::pow3<Foam::fvPatchField, Foam::volMesh>(Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh>&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) at ??:?
[38] #5  Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam::pow3<Foam::fvPatchField, Foam::volMesh>(Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) at ??:?
[38] #6  Foam::LESModels::WALE<Foam::incompressibleMomentumTransportModel>::k(Foam::GeometricField<Foam::Tensor<double>, Foam::fvPatchField, Foam::volMesh> const&) const at ??:?
[38] #7  Foam::LESModels::WALE<Foam::incompressibleMomentumTransportModel>::correctNut() at ??:?
[38] #8  ? at ??:?
[38] #9  __libc_start_main in "/lib64/libc.so.6"
[38] #10  ? at ??:?
[m3cn2707:519656:0:519656] Caught signal 8 (Floating point exception: tkill(2) or tgkill(2))
==== backtrace ====
    0  /usr/lib64/libucs.so.0(+0x17970) [0x2b9da57c4970]
    1  /usr/lib64/libucs.so.0(+0x17c23) [0x2b9da57c4c23]
    2  /lib64/libc.so.6(gsignal+0x37) [0x2b9c34fa7387]
    3  /public1/home/sch10341/soft/openfoam10/OpenFOAM-10/platforms/linux64IcxDPInt32Opt/lib/libOpenFOAM.so(_ZN4Foam4pow3ERNS_5FieldIdEERKNS_5UListIdEE+0xae) [0x2b9c340b32ee]
    4  /public1/home/sch10341/soft/openfoam10/OpenFOAM-10/platforms/linux64IcxDPInt32Opt/lib/libincompressibleMomentumTransportModels.so(_ZN4Foam4pow3INS_12fvPatchFieldENS_7volMeshEEEvRNS_14GeometricFieldIdT_T0_EERKS6_+0x31) [0x2b9c30c1c421]
    5  /public1/home/sch10341/soft/openfoam10/OpenFOAM-10/platforms/linux64IcxDPInt32Opt/lib/libincompressibleMomentumTransportModels.so(_ZN4Foam4pow3INS_12fvPatchFieldENS_7volMeshEEENS_3tmpINS_14GeometricFieldIdT_T0_EEEERKS7_+0x188) [0x2b9c30c1bad8]
    6  /public1/home/sch10341/soft/openfoam10/OpenFOAM-10/platforms/linux64IcxDPInt32Opt/lib/libincompressibleMomentumTransportModels.so(_ZNK4Foam9LESModels4WALEINS_36incompressibleMomentumTransportModelEE1kERKNS_14GeometricFieldINS_6TensorIdEENS_12fvPatchFieldENS_7volMeshEEE+0x758) [0x2b9c30cb6da8]
    7  /public1/home/sch10341/soft/openfoam10/OpenFOAM-10/platforms/linux64IcxDPInt32Opt/lib/libincompressibleMomentumTransportModels.so(_ZN4Foam9LESModels4WALEINS_36incompressibleMomentumTransportModelEE10correctNutEv+0x12d) [0x2b9c30cb637d]
    8  simpleFoam() [0x43326c]
    9  /lib64/libc.so.6(__libc_start_main+0xf5) [0x2b9c34f93555]
   10  simpleFoam() [0x41c588]
===================

1、checkMesh结果如图所示：
case1：

case2：

2、blcokMeshDict文件如下所示:
case1：

backgroundMesh
{
    xMin   4000; 
    xMax   6100;
    yMin   4400; 
    yMax   6500;
    zMin     -60;
    zMax   600;
    xCells  70;
    yCells  70;
    zCells  22;
}

convertToMeters 1;

vertices
(
    ($!backgroundMesh/xMin $!backgroundMesh/yMin $!backgroundMesh/zMin)
    ($!backgroundMesh/xMax $!backgroundMesh/yMin $!backgroundMesh/zMin)
    ($!backgroundMesh/xMax $!backgroundMesh/yMax $!backgroundMesh/zMin)
    ($!backgroundMesh/xMin $!backgroundMesh/yMax $!backgroundMesh/zMin)

    ($!backgroundMesh/xMin $!backgroundMesh/yMin $!backgroundMesh/zMax)
    ($!backgroundMesh/xMax $!backgroundMesh/yMin $!backgroundMesh/zMax)
    ($!backgroundMesh/xMax $!backgroundMesh/yMax $!backgroundMesh/zMax)
    ($!backgroundMesh/xMin $!backgroundMesh/yMax $!backgroundMesh/zMax)
);

blocks
(
    hex (0 1 2 3 4 5 6 7)
    (
        $!backgroundMesh/xCells
        $!backgroundMesh/yCells
        $!backgroundMesh/zCells
    )
    simpleGrading (1 1 1)
);

boundary
(
    west
    {
        type patch;
        faces
        (
            (0 3 7 4)
        );
    }

    east
    {
        type patch;
        faces
        (
            (1 5 6 2)
        );
    }


    south
    {
        type patch;
        faces
        (
            (0 4 5 1)
        );
    }
    north
    {
        type patch;
        faces
        (
            (3 2 6 7)
        );
    }

    ground
    {
        type wall;
        faces
        (
            (0 1 2 3)
        );
    }

    top
    {
        type patch;
        faces
        (
            (4 7 6 5)
        );
    }

);

case2：（只修改了xmin,xmax,ymin,ymax）

backgroundMesh
{
backgroundMesh
    {
        xMin   3500; 
        xMax   6500;
        yMin   4000; 
        yMax   7000;
        zMin     -60;
        zMax   600;
        xCells  100;
        yCells  100;
        zCells  22;
    }
    
    convertToMeters 1;
    
    vertices
    (
        ($!backgroundMesh/xMin $!backgroundMesh/yMin $!backgroundMesh/zMin)
        ($!backgroundMesh/xMax $!backgroundMesh/yMin $!backgroundMesh/zMin)
        ($!backgroundMesh/xMax $!backgroundMesh/yMax $!backgroundMesh/zMin)
        ($!backgroundMesh/xMin $!backgroundMesh/yMax $!backgroundMesh/zMin)
    
        ($!backgroundMesh/xMin $!backgroundMesh/yMin $!backgroundMesh/zMax)
        ($!backgroundMesh/xMax $!backgroundMesh/yMin $!backgroundMesh/zMax)
        ($!backgroundMesh/xMax $!backgroundMesh/yMax $!backgroundMesh/zMax)
        ($!backgroundMesh/xMin $!backgroundMesh/yMax $!backgroundMesh/zMax)
    );
    
    blocks
    (
        hex (0 1 2 3 4 5 6 7)
        (
            $!backgroundMesh/xCells
            $!backgroundMesh/yCells
            $!backgroundMesh/zCells
        )
        simpleGrading (1 1 1)
    );
    
    boundary
    (
        west
        {
            type patch;
            faces
            (
                (0 3 7 4)
            );
        }
    
        east
        {
            type patch;
            faces
            (
                (1 5 6 2)
            );
        }
    
    
        south
        {
            type patch;
            faces
            (
                (0 4 5 1)
            );
        }
        north
        {
            type patch;
            faces
            (
                (3 2 6 7)
            );
        }
    
        ground
        {
            type wall;
            faces
            (
                (0 1 2 3)
            );
        }
    
        top
        {
            type patch;
            faces
            (
                (4 7 6 5)
            );
        }
    
    );
}

3、snappyHexMeshDict文件如下：


// Which of the steps to run
castellatedMesh true;
snap            true;
addLayers       false;


// Geometry. Definition of all surfaces. All surfaces are of class
// searchableSurface.
// Surfaces are used
// - to specify refinement for any mesh cell intersecting it
// - to specify refinement for any mesh cell inside/outside/near
// - to 'snap' the mesh boundary to the surface
geometry
{
    terrain
    {
        type triSurfaceMesh;
        file "km8LS.stl";
    }
};



// Settings for the castellatedMesh generation.
castellatedMeshControls
{

    // Refinement parameters
    // ~~~~~~~~~~~~~~~~~~~~~

    // If local number of cells is >= maxLocalCells on any processor
    // switches from from refinement followed by balancing
    // (current method) to (weighted) balancing before refinement.
    maxLocalCells 100000;

    // Overall cell limit (approximately). Refinement will stop immediately
    // upon reaching this number so a refinement level might not complete.
    // Note that this is the number of cells before removing the part which
    // is not 'visible' from the keepPoint. The final number of cells might
    // actually be a lot less.
    maxGlobalCells 2000000;

    // The surface refinement loop might spend lots of iterations
    // refining just a few cells. This setting will cause refinement
    // to stop if <= minimumRefine are selected for refinement. Note:
    // it will at least do one iteration (unless the number of cells
    // to refine is 0)
    minRefinementCells 0;

    // Allow a certain level of imbalance during refining
    // (since balancing is quite expensive)
    // Expressed as fraction of perfect balance (= overall number of cells /
    // nProcs). 0=balance always.
    maxLoadUnbalance 0.10;


    // Number of buffer layers between different levels.
    // 1 means normal 2:1 refinement restriction, larger means slower
    // refinement.
    nCellsBetweenLevels 1;



    // Explicit feature edge refinement
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    // Specifies a level for any cell intersected by its edges.
    // This is a featureEdgeMesh, read from constant/geometry for now.
    features
    (
        //{
        //    file "someLine.eMesh";
        //    level 2;
        //}
    );



    // Surface based refinement
    // ~~~~~~~~~~~~~~~~~~~~~~~~

    // Specifies two levels for every surface. The first is the minimum level,
    // every cell intersecting a surface gets refined up to the minimum level.
    // The second level is the maximum level. Cells that 'see' multiple
    // intersections where the intersections make an
    // angle > resolveFeatureAngle get refined up to the maximum level.

    refinementSurfaces
    {
        terrain
        {
            // Surface-wise min and max refinement level
            level (2 2);

            // Optional region-wise level specification
/*
            regions
            {
                windTurbine
                {
                    level (3 3);
                }
            }
*/
            //- Optional angle to detect small-large cell situation
            //  perpendicular to the surface. Is the angle of face w.r.t.
            //  the local surface normal. Use on flat(ish) surfaces only.
            //  Otherwise leave out or set to negative number.
            // perpendicularAngle 10;


            //- Optional faceZone and (for closed surface) cellZone with
            //  how to select the cells that are in the cellZone
            //  (inside / outside / specified insidePoint)
            // faceZone sphere;
            // cellZone sphere;
            // mode        inside;  // outside/insidePoint
        }
    }

    resolveFeatureAngle 30;


    // Region-wise refinement
    // ~~~~~~~~~~~~~~~~~~~~~~

    // Specifies refinement level for cells in relation to a surface. One of
    // three modes
    // - distance. 'levels' specifies per distance to the surface the
    //   wanted refinement level. The distances need to be specified in
    //   descending order.
    // - inside. 'levels' is only one entry and only the level is used. All
    //   cells inside the surface get refined up to the level. The surface
    //   needs to be closed for this to be possible.
    // - outside. Same but cells outside.

    refinementRegions
    {



        // sphere.stl
        //{
        //    mode distance;
        //    levels ((1.0 5) (2.0 3));
        //}
    }


    // Mesh selection
    // ~~~~~~~~~~~~~~

    // After refinement patches get added for all refinementSurfaces and
    // all cells intersecting the surfaces get put into these patches. The
    // section reachable from the insidePoint is kept.
    // NOTE: This point should never be on a face, always inside a cell, even
    // after refinement.
    insidePoint (5000 5500 300);


    // Whether any faceZones (as specified in the refinementSurfaces)
    // are only on the boundary of corresponding cellZones or also allow
    // free-standing zone faces. Not used if there are no faceZones.
    allowFreeStandingZoneFaces true;
}



// Settings for the snapping.
snapControls
{
    //- Number of patch smoothing iterations before finding correspondence
    //  to surface
    nSmoothPatch 3;

    //- Relative distance for points to be attracted by surface feature point
    //  or edge. True distance is this factor times local
    //  maximum edge length.
    tolerance 4.0;

    //- Number of mesh displacement relaxation iterations.
    nSolveIter 30;

    //- Maximum number of snapping relaxation iterations. Should stop
    //  before upon reaching a correct mesh.
    nRelaxIter 5;
}



// Settings for the layer addition.
addLayersControls
{
    // Are the thickness parameters below relative to the undistorted
    // size of the refined cell outside layer (true) or absolute sizes (false).
    relativeSizes true;

    // Per final patch (so not geometry!) the layer information
    layers
    {
    }

    // Expansion factor for layer mesh
    expansionRatio 1.0;


    // Wanted thickness of final added cell layer. If multiple layers
    // is the thickness of the layer furthest away from the wall.
    // Relative to undistorted size of cell outside layer.
    // See relativeSizes parameter.
    finalLayerThickness 0.3;

    // Minimum thickness of cell layer. If for any reason layer
    // cannot be above minThickness do not add layer.
    // See relativeSizes parameter.
    minThickness 0.25;

    // If points get not extruded do nGrow layers of connected faces that are
    // also not grown. This helps convergence of the layer addition process
    // close to features.
    // Note: changed(corrected) w.r.t 17x! (didn't do anything in 17x)
    nGrow 0;


    // Advanced settings

    // When not to extrude surface. 0 is flat surface, 90 is when two faces
    // are perpendicular
    featureAngle 60;

    // Maximum number of snapping relaxation iterations. Should stop
    // before upon reaching a correct mesh.
    nRelaxIter 5;

    // Number of smoothing iterations of surface normals
    nSmoothSurfaceNormals 1;

    // Number of smoothing iterations of interior mesh movement direction
    nSmoothNormals 3;

    // Smooth layer thickness over surface patches
    nSmoothThickness 10;

    // Stop layer growth on highly warped cells
    maxFaceThicknessRatio 0.5;

    // Reduce layer growth where ratio thickness to medial
    // distance is large
    maxThicknessToMedialRatio 0.3;

    // Angle used to pick up medial axis points
    // Note: changed(corrected) w.r.t 16x! 90 degrees corresponds to 130 in 16x.
    minMedianAxisAngle 90;

    // Create buffer region for new layer terminations
    nBufferCellsNoExtrude 0;


    // Overall max number of layer addition iterations. The mesher will exit
    // if it reaches this number of iterations; possibly with an illegal
    // mesh.
    nLayerIter 50;

    // Max number of iterations after which relaxed meshQuality controls
    // get used. Up to nRelaxIter it uses the settings in meshQualityControls,
    // after nRelaxIter it uses the values in meshQualityControls::relaxed.
    nRelaxedIter 20;
}



// Generic mesh quality settings. At any undoable phase these determine
// where to undo.
meshQualityControls
{
    //- Maximum non-orthogonality allowed. Set to 180 to disable.
    maxNonOrtho 65;

    //- Max skewness allowed. Set to <0 to disable.
    maxBoundarySkewness 20;
    maxInternalSkewness 4;

    //- Max concaveness allowed. Is angle (in degrees) below which concavity
    //  is allowed. 0 is straight face, <0 would be convex face.
    //  Set to 180 to disable.
    maxConcave 80;

    //- Minimum cell pyramid volume relative to min bounding box length^3
    //  Set to a fraction of the smallest cell volume expected.
    //  Set to very negative number (e.g. -1e30) to disable.
    minVol -1e30;

    //- Minimum quality of the tet formed by the face-centre
    //  and variable base point minimum decomposition triangles and
    //  the cell centre.  Set to very negative number (e.g. -1e30) to
    //  disable.
    //     <0 = inside out tet,
    //      0 = flat tet
    //      1 = regular tet
    minTetQuality 1e-30;

    //- Minimum face twist. Set to <-1 to disable. dot product of face normal
    //  and face centre triangles normal
    minTwist 0.05;

    //- Minimum normalised cell determinant
    //  1 = hex, <= 0 = folded or flattened illegal cell
    minDeterminant 0.001;

    //- minFaceWeight (0 -> 0.5)
    minFaceWeight 0.05;

    //- minVolRatio (0 -> 1)
    minVolRatio 0.01;

    //- Number of error distribution iterations
    nSmoothScale 4;

    //- Amount to scale back displacement at error points
    errorReduction 0.75;

    relaxed
    {
        //- Maximum non-orthogonality allowed. Set to 180 to disable.
        maxNonOrtho 75;
    }
}

mergeTolerance 1e-6;

wsy11

@coolhhh
大佬您好，我可能忘了介绍我的研究时段了，我研究的是较长时间的模拟，理想模拟时间应该是2-3天；模拟区域也比较大，大概为长宽高为6km6km600m。
1、因为研究的时间较长，所以每个边界的风速肯定是变化的（风速输入用的是每个边界所设置的非均匀分布风塔的观测数据，每个面都有数个观测点，观测数据风速利用timeVaryingMappedFixedValue每隔十分钟输入）因为之前学习了windaroundbuildings这个算例（也是建筑扰流），所以设置求解器为simpleFoam，这个算例风速确实是时不变的，这一点没有考虑到，等换成瞬时求解器试试；
2、目前还没有试过五个入流面，因为我也认为可能不太符合通量守恒，所以先设置了3个速度入口和2个出口，我先做一下大佬在4中提供的建议；
3、LES模拟也考虑过，正在学习，等做完2中试验后尝试一下大佬提供的条件，就不用计算k和epsilon文件的设置了。

wsy11

@李东岳
李老师您好，我刚实操OpenFOAM，不太确定是否为您说的单向流求解器：
1、我的研究区域top、west、east、south、north面的速度都是已知的，因此理论上应该把除地面外的五个面都设置好初始速度，我要做的工作就是把大尺度的风速给细化，得到研究区域区域内小尺度的风速（即复杂地形的建筑物扰流）；
2、我也认为是湍流的边界条件问题，今天学习后发现可能是因为将入口设置为时变的非均匀速度条件后，并没有改变k文件和epsilon文件对应点位的值（如上边对应文件所示，k和epsilon只是简单的设置成了fixedValue）；
3、李老师，想请问您一个问题：如果设置好入流面一个点的（u，v，w）后，这个点的脉动速度分别为（0.05u,0.05v，0.05w）吗？对于下面图中的k和速度场U的关系不是很理解

wsy11

@coolhhh
大佬您好，感谢您的指导，以下我对于没说清楚的点的一些解释：
1、是的，我是计算的复杂地形上的建筑绕流，，但是不确定是否为URANS，我刚刚接触CFD，还没有具体学过湍流求解方法，现在选择RAS只是想先跑出结果；
2、top面设置为速度入口，是因为我的研究区域，top、west、east、south、north面的速度都是已知的，因此把top面速度条件也给加进去了（理论上应该把除地面外的五个面都设置好初始速度），我要做的工作就是把大尺度的风速给细化，得到研究区域区域内小尺度的风速；
3、zeroGradient这个条件也试过，但是还是发散，经过今天的学习，我认为是k文件epsilon文件的初始值也需要更改，准备以后测试一下。
最后再次感谢大佬的耐心指导！（刚接触CFD，可能对于一些问题的解释并不是很清楚）

wsy11

请教各位老师一个边界条件文件，如题，我对于速度条件使用了在网上搜到的timeVaryingMappedFixedValue条件，可以导入时变、非均匀的风速数据，但是运行后会报发散错误，我认为是因为没有修改其他物理量边界条件的问题，但是没有找到相关的解决方法。
希望各位老师帮忙看下怎么修改对应的边界条件：
blockMesh如下：

backgroundMesh
{
    xMin   1250; 
    xMax   8698;
    yMin   1343; 
    yMax   9476;
    zMin     -60;
    zMax   600;
    xCells  248;
    yCells  271;
    zCells  33;
}

convertToMeters 1;

vertices
(
    ($!backgroundMesh/xMin $!backgroundMesh/yMin $!backgroundMesh/zMin)
    ($!backgroundMesh/xMax $!backgroundMesh/yMin $!backgroundMesh/zMin)
    ($!backgroundMesh/xMax $!backgroundMesh/yMax $!backgroundMesh/zMin)
    ($!backgroundMesh/xMin $!backgroundMesh/yMax $!backgroundMesh/zMin)

    ($!backgroundMesh/xMin $!backgroundMesh/yMin $!backgroundMesh/zMax)
    ($!backgroundMesh/xMax $!backgroundMesh/yMin $!backgroundMesh/zMax)
    ($!backgroundMesh/xMax $!backgroundMesh/yMax $!backgroundMesh/zMax)
    ($!backgroundMesh/xMin $!backgroundMesh/yMax $!backgroundMesh/zMax)
);

blocks
(
    hex (0 1 2 3 4 5 6 7)
    (
        $!backgroundMesh/xCells
        $!backgroundMesh/yCells
        $!backgroundMesh/zCells
    )
    simpleGrading (1 1 1)
);

boundary
(
    west
    {
        type patch;
        faces
        (
            (0 3 7 4)
        );
    }

    east
    {
        type patch;
        faces
        (
            (1 5 6 2)
        );
    }


    south
    {
        type patch;
        faces
        (
            (0 4 5 1)
        );
    }
    north
    {
        type patch;
        faces
        (
            (3 2 6 7)
        );
    }

    ground
    {
        type wall;
        faces
        (
            (0 1 2 3)
        );
    }

    top
    {
        type patch;
        faces
        (
            (4 7 6 5)
        );
    }

);

各物理量边界条件如下：
U

dimensions      [0 1 -1 0 0 0 0];

internalField   uniform (0 0 0);

boundaryField
{
    west
    {
        type            timeVaryingMappedFixedValue;
        offset          (0 0 0);
        setAverage      off;

    }
    east
    {
        type            pressureInletOutletVelocity;
        value           uniform (0 0 0);
    }
    north
    {
        type            timeVaryingMappedFixedValue;
        offset          (0 0 0);
        setAverage      off;

    }
    south
    {
        type            pressureInletOutletVelocity;
        value           uniform (0 0 0);
    }
    ground
    {
        type            noSlip;
    }
    buildings
    {
        type            noSlip;
    }
     wall
    {
        type            noSlip;
    }
    top
    {
        type            timeVaryingMappedFixedValue;
        offset          (0 0 0);
        setAverage      off;
    }
}

P

dimensions      [0 2 -2 0 0 0 0];

internalField   uniform 0;

boundaryField
{
    west
    {
        type            zeroGradient;
    }
    east
    {
        type            totalPressure;
        rho             rho;
        psi             none;
        gamma           1;
        p0              uniform 0;
        value           uniform 0;
    }
    north
    {
        type            zeroGradient;
    }
    south
    {
        type            totalPressure;
        rho             rho;
        psi             none;
        gamma           1;
        p0              uniform 0;
        value           uniform 0;
    }
    ground
    {
        type            zeroGradient;
    }
    wall
    {
        type            zeroGradient;
    }
    buildings
    {
        type            zeroGradient;
    }
    top
    {
        type            zeroGradient;
    }
}

nut

dimensions      [0 2 -1 0 0 0 0];

internalField   uniform 0;

boundaryField
{
    west
    {
        type            calculated;
        value           uniform 0;
    }
    east
    {
        type            calculated;
        value           uniform 0;
    }
    north
    {
        type            calculated;
        value           uniform 0;
    }
    south
    {
        type            calculated;
        value           uniform 0;
    }
    ground
    {
        type            nutkWallFunction;
        value           uniform 0;
    }
    buildings
    {
        type            nutkWallFunction;
        value           uniform 0;
    }
    wall
    {
        type            nutkWallFunction;
        value           uniform 0;
    }

    top
    {
        type            calculated;
        value           uniform 0;
    }
}

k

dimensions      [0 2 -2 0 0 0 0];

internalField   uniform 1.5;

boundaryField
{
    west
    {
        type            fixedValue;
        value           uniform 1.5;
    }
    east
    {
        type            inletOutlet;
        inletValue      uniform 1.5;
        value           uniform 1.5;
    }
    north
    {
        type            fixedValue;
        value           uniform 1.5;
    }
    south
    {
        type            inletOutlet;
        inletValue      uniform 1.5;
        value           uniform 1.5;
    }
    ground
    {
        type            kqRWallFunction;
        value           uniform 1.5;
    }
    buildings
    {
        type            kqRWallFunction;
        value           uniform 1.5;
    }
    wall
    {
        type            kqRWallFunction;
        value           uniform 1.5;
    }

    top
    {
        type            inletOutlet;
        inletValue      uniform 1.5;
        value           uniform 1.5;
    }
}

spsilon

dimensions      [0 2 -3 0 0 0 0];

internalField   uniform 0.03;

boundaryField
{
    west
    {
        type            fixedValue;
        value           uniform 0.03;
    }
    east
    {
        type            inletOutlet;
        inletValue      uniform 0.03;
        value           uniform 0.03;
    }
    north
    {
        type            fixedValue;
        value           uniform 0.03;
    }
    south
    {
        type            inletOutlet;
        inletValue      uniform 0.03;
        value           uniform 0.03;
    }
    ground
    {
        type            epsilonWallFunction;
        value           uniform 0.03;
    }
    buildings
    {
        type            epsilonWallFunction;
        value           uniform 0.03;
    }
    wall
    {
        type            epsilonWallFunction;
        value           uniform 0.03;
    }

    top
    {
        type            inletOutlet;
        inletValue      uniform 0.03;
        value           uniform 0.03;
    }
}

wsy11

@星星星星晴谢谢您，问题解决了，尝试了很多方法，没想到问题出在分号上，以后还是得更认真一点

wsy11

@星星星星晴这个视频我已经看过了，也参考了视频中的步骤。
我把目录改成英文以后还是同样的报错，
我在其他的地方没有什么改动，都是用的tutorials\incompressible\simpleFoam\windaroundbuildings算例自带的条件。
，

wsy11

@星星星星晴大佬您好，我学习了您的教程，但是没有复现出来，您能帮我看看哪出问题了吗？
我是用的of10，直接修改的windaroundbuidings算例（只改了速度U）
U文件如下

/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  10
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    format      ascii;
    class       volVectorField;
    object      U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

Uinlet          (10 0 0);

dimensions      [0 1 -1 0 0 0 0];

internalField   uniform (0 0 0);

boundaryField
{
    inlet
    {
        type            fixedValue;
        value           nonuniform List<vector>
494
(
( -1.2961   0.0000   0.0000) 
( -0.7059   0.0000   0.0000) 
( -0.2917   0.0000   0.0000) 
( -0.0393   0.0000   0.0000) 
(  0.0672   0.0000   0.0000) 
(  0.1305   0.0000   0.0000) 
(  0.1642   0.0000   0.0000) 
(  0.1796   0.0000   0.0000) 
(  0.1850   0.0000   0.0000) 
.......
........
(  0.3551   0.0000   0.0000) 
(  0.3592   0.0000   0.0000) 
( -0.2114   0.0000   0.0000) 
(  0.1055   0.0000   0.0000) 
(  0.1069   0.0000   0.0000) 
(  0.1057   0.0000   0.0000) 
( -0.2113   0.0000   0.0000) 
( -0.2135   0.0000   0.0000) 
)
    }

    outlet
    {
        type            pressureInletOutletVelocity;
        value           uniform (0 0 0);
    }

    wall
    {
        type            noSlip;
    }

    #includeEtc "caseDicts/setConstraintTypes"
}

报错如下：

wsy11

@上级大佬，想问下cfMesh上手难吗？我在做相似的研究，想转成cfMesh试一下

wsy11

请教各位大佬一个边界条件的选择问题
我的研究区域是一个三维区域，长宽高分别为（6000m*6000m*600m），如下图（俯视图）所示：

图中的红色点是在研究区域内的观测站点，每一个观测点位可以得到从地面到600m高度处的风速、气压、温度等数据，
请问应该选择什么边界条件来把这些观测点位的数据输入到openfoam中？

wsy11

@dyb 在 pointwise划分了地形网格计算域为3000*3000*1000 ，用openFoam中simpleFoam求解计算错误？中说：

pointwise绘制计算域，把边界层加大一些

大佬您好，我想再请教一个问题
turbinesiting算例中的地形的stl文件是怎么生成的？我用自己的stl文件（用GlobalMapper裁剪ASTER GDEM地形高程数据）时，会存在两个底面，terrian面和ground面都会存在。

wsy11

@dyb 好的好的，谢谢大佬。
我目前的网格划分还比较简单，是用GlobalMapper裁剪ASTER GDEM地形高程数据，然后用snappyHexMesh工具自动划分网格的，还没学过pointwise，等我尝试一下您的方法再来请教。

wsy11

@dyb 在 pointwise划分了地形网格计算域为3000*3000*1000 ，用openFoam中simpleFoam求解计算错误？中说：
大佬您好，
我最近也在学习复杂地形上风场的模拟，使用的也是turbinesiting这个算例，请问这个算例有没有比较好的教程？
目前还是小白，总是会报错

CFD中文网

wsy11

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