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@李东岳 李老师 我用bouyantBoussinesqPimpleFoam算了一下 看起来更合理 是不是就说明跟是否可压有关？

请教下各位老师
我在计算二维山地风场 同时考虑温度 目前buoyantPimpleFoam计算一直发散

我把重力g设置成0的话 计算也会发散 但是速度场看起来会比较正常 是压力的问题吗？

@李东岳 手动艾特下大佬

@疏影横斜水清浅 老师 已经给您发过邮件了

@疏影横斜水清浅 您好 刚看了下您的帖子 我跟您的课题相似 可以加个联系方式请教下吗

@coolhhh 我去试下 谢谢老师指点

@coolhhh 老师 边界条件的具体数值跟网格尺寸互相有什么影响吗 能不能是我换网格之后 u k e这种值给错了

@coolhhh 老师 我的网格就是二维矩形 大小均匀 只是数量更多 计算域更大了 会是质量问题吗

顶一下 更换更大计算域 更多网格 需要该边界条件的数值和离散格式吗？

@李东岳 李老师，我看这个新网格质量也OK。是需要改离散格式边界条件这些，还是说对于这求解器我的新网格不过关？

请教下各位老师，换了个其他模型的网格，网格数更多，条件全都一样，计算发散是为什么？有什么需要修改的吗？
原网格

Create time

Create mesh for time = 0

Time = 0

Mesh stats
    points:           16482
    internal points:  0
    faces:            32240
    internal faces:   15760
    cells:            8000
    faces per cell:   6
    boundary patches: 7
    point zones:      0
    face zones:       0
    cell zones:       0

Overall number of cells of each type:
    hexahedra:     8000
    prisms:        0
    wedges:        0
    pyramids:      0
    tet wedges:    0
    tetrahedra:    0
    polyhedra:     0

Checking topology...
    Boundary definition OK.
    Cell to face addressing OK.
    Point usage OK.
    Upper triangular ordering OK.
    Face vertices OK.
    Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
    Patch               Faces    Points   Surface topology                  
    inletTop            4        10       ok (non-closed singly connected)  
    inletBottom         4        10       ok (non-closed singly connected)  
    outletTop           4        10       ok (non-closed singly connected)  
    walls               464      936      ok (non-closed singly connected)  
    front               8000     8241     ok (non-closed singly connected)  
    back                8000     8241     ok (non-closed singly connected)  
    outletBottom        4        10       ok (non-closed singly connected)  

Checking faceZone topology for multiply connected surfaces...
    No faceZones found.

Checking basic cellZone addressing...
    No cellZones found.

Checking geometry...
    Overall domain bounding box (-3.88578e-16 2.27374e-15 0) (10 2 0.2)
    Mesh has 2 geometric (non-empty/wedge) directions (1 1 0)
    Mesh has 2 solution (non-empty) directions (1 1 0)
    All edges aligned with or perpendicular to non-empty directions.
    Boundary openness (-2.71051e-19 2.43945e-18 6.33e-17) OK.
    Max cell openness = 1.73472e-16 OK.
    Max aspect ratio = 1 OK.
    Minimum face area = 0.0025. Maximum face area = 0.01.  Face area magnitudes OK.
    Min volume = 0.0005. Max volume = 0.0005.  Total volume = 4.  Cell volumes OK.
    Mesh non-orthogonality Max: 0 average: 0
    Non-orthogonality check OK.
    Face pyramids OK.
    Max skewness = 1.77636e-13 OK.
    Coupled point location match (average 0) OK.

Mesh OK.

End

新网格

Create time

Create mesh for time = 0

Time = 0

Mesh stats
    points:           486356
    internal points:  0
    faces:            968451
    internal faces:   482097
    cells:            241758
    faces per cell:   6
    boundary patches: 5
    point zones:      0
    face zones:       0
    cell zones:       0

Overall number of cells of each type:
    hexahedra:     241758
    prisms:        0
    wedges:        0
    pyramids:      0
    tet wedges:    0
    tetrahedra:    0
    polyhedra:     0

Checking topology...
    Boundary definition OK.
    Cell to face addressing OK.
    Point usage OK.
    Upper triangular ordering OK.
    Face vertices OK.
    Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
    Patch               Faces    Points   Surface topology                  
    INLET               198      398      ok (non-closed singly connected)  
    OUTLET              198      398      ok (non-closed singly connected)  
    TOP                 1221     2444     ok (non-closed singly connected)  
    WALL                1221     2444     ok (non-closed singly connected)  
    frontAndBack        483516   486356   ok (non-closed singly connected)  

Checking faceZone topology for multiply connected surfaces...
    No faceZones found.

Checking basic cellZone addressing...
    No cellZones found.

Checking geometry...
    Overall domain bounding box (-3500 0 0) (10500 4000 15.7505)
    Mesh has 2 geometric (non-empty/wedge) directions (1 1 0)
    Mesh has 2 solution (non-empty) directions (1 1 0)
    All edges aligned with or perpendicular to non-empty directions.
    Boundary openness (9.7422e-20 2.77781e-17 4.16351e-14) OK.
    Max cell openness = 3.24713e-16 OK.
    Max aspect ratio = 629.147 OK.
    Minimum face area = 1. Maximum face area = 61981.3.  Face area magnitudes OK.
    Min volume = 15.7505. Max volume = 976235.  Total volume = 8.80452e+08.  Cell volumes OK.
    Mesh non-orthogonality Max: 32.1987 average: 12.372
    Non-orthogonality check OK.
    Face pyramids OK.
    Max skewness = 0.231851 OK.
    Coupled point location match (average 0) OK.

Mesh OK.

End

@coolhhh 谢谢老师！

@coolhhh 您好，我想用toposet createpatch弄一个口，然后设置U（0 -10 0），您觉得可行吗

@coolhhh 谢谢解答 这就去学习下

@coolhhh 谢指教。通过边界条件的话 是不是要在构建几何模型的时候就掏一个区域？如果加源项大概是什么样？要在哪里修改？

@coolhhh 您好 如果这样的话 wall会不会影响流场？ 如果加一个非均匀的内部场 或者通过mapfields可行吗？

@李东岳 东岳老师帮帮我

请教下各位老师，我想在流场内某一处加一个气流，来模仿旋翼产生的下洗流场，应该怎么实现呢？加一个速度就行，但是要持续存在。模型是二维的。

请教下，算到第二步就报浮点异常，是边界调节设置错了吗？

想看拉格朗日粒子paraview不能看，parafoam就这样，我用的是ubuntu22.04.4和of11，该怎么编译parafoam？请教下

用的windAroundBuildings算例，840万网格的二维模型，网格质量检查过了，计算域是14000*4000米。epsilonInlet 0.0003; // Cmu^0.75 * k^1.5 / L ; L =10

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

internalField uniform $epsilonInlet;

boundaryField
{
INLET
{
type fixedValue;
value uniform $epsilonInlet;
}

OUTLET
{
    type            zeroGradient;

}

WALL
{
    type            epsilonWallFunction;
    value           uniform $epsilonInlet;
}
frontAndBackPlanes
{
    type            empty;
}
#includeEtc "caseDicts/setConstraintTypes"

}
kInlet 1.5; // approx k = 1.5*(I*U)^2 ; I = 0.1

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

internalField uniform $kInlet;

boundaryField
{
INLET
{
type fixedValue;
value uniform $kInlet;
}
OUTLET
{
type zeroGradient;
}

WALL
{
    type            kqRWallFunction;
    value           uniform $kInlet;
}
frontAndBackPlanes
{
    type            empty;
}
#includeEtc "caseDicts/setConstraintTypes"

}
nut
internalField uniform 0;

boundaryField
{
INLET
{
type calculated;
value uniform 0;
}

OUTLET
{
    type            calculated;
    value           uniform 0;
}

WALL
{
    type            nutUSpaldingWallFunction;
    value           uniform 0;
}
frontAndBackPlanes
{
    type            empty;
}
#includeEtc "caseDicts/setConstraintTypes"

}
p
internalField uniform 0;

boundaryField
{
INLET
{
type zeroGradient;
}
OUTLET
{
type fixedValue;
value uniform 0;
p0 uniform 0;
}
WALL
{
type zeroGradient;
}
frontAndBackPlanes
{
type empty;
}

#includeEtc "caseDicts/setConstraintTypes"

}
Uinlet (10 0 0);

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

internalField uniform (10 0 0);

boundaryField
{
INLET
{
type fixedValue;
value uniform $Uinlet;
}
OUTLET
{
type zeroGradient;
}

WALL
{
    type            noSlip;
}
frontAndBackPlanes
{
    type            empty;
}

#includeEtc "caseDicts/setConstraintTypes"

}
时间步长试过1 0.1 0.01 其他的都没动