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有没有其他大佬，半个多月了，求问一下。还有没有大佬吱一声

求大佬看看！

Added patches in = 0.02 s

Edge intersection testing:
    Number of edges             : 5008207
    Number of edges to retest   : 490832
    Number of intersected edges : 475794
Decomposition method none [1]

Refinement phase
----------------

Found point (10 20 5) in cell 587820 on processor 0

Feature refinement iteration 0
------------------------------

Marked for refinement due to explicit features             : 6 cells.
Determined cells to refine in = 9.79 s
Selected for feature refinement : 13 cells (out of 1506875)
Edge intersection testing:
    Number of edges             : 5008546
    Number of edges to retest   : 781
    Number of intersected edges : 475794
Refined mesh in = 2.28 s
After refinement feature refinement iteration 0 : cells:1506966  faces:5008546  points:2028784
Cells per refinement level:
    0   438931
    1   42098
    2   131721
    3   456157
    4   438059

Feature refinement iteration 1
------------------------------

Marked for refinement due to explicit features             : 0 cells.
Determined cells to refine in = 9.22 s
Selected for feature refinement : 0 cells (out of 1506966)
Stopping refining since too few cells selected.


Surface refinement iteration 0
------------------------------

Marked for refinement due to surface intersection          : 27528 cells.
Determined cells to refine in = 0.62 s
Selected for refinement : 29733 cells (out of 1506966)
hexRef8 : Dumping cell as obj to "/mnt/g/City4CFD/City4CFD/examples/TUDCampus/c4c_tst_20240924/cell_813430.obj"


--> FOAM FATAL ERROR: (openfoam-2312)
cell 813430 of level 2 uses more than 8 points of equal or lower level
Points so far:8(467622 506063 542474 660192 812094 865708 953356 1395965)

    From Foam::labelListList Foam::hexRef8::setRefinement(const labelList&, Foam::polyTopoChange&)
    in file polyTopoChange/polyTopoChange/hexRef8/hexRef8.C at line 3604.

FOAM aborting

[stack trace]
=============
#1  Foam::error::simpleExit(int, bool) in ~/OpenFOAM-v2312/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so
#2  Foam::hexRef8::setRefinement(Foam::List<int> const&, Foam::polyTopoChange&) in ~/OpenFOAM-v2312/platforms/linux64GccDPInt32Opt/lib/libdynamicMesh.so
#3  Foam::meshRefinement::refine(Foam::List<int> const&) in ~/OpenFOAM-v2312/platforms/linux64GccDPInt32Opt/lib/libsnappyHexMesh.so
#4  Foam::meshRefinement::balanceAndRefine(Foam::string const&, Foam::decompositionMethod&, Foam::fvMeshDistribute&, Foam::List<int> const&, double, int) in ~/OpenFOAM-v2312/platforms/linux64GccDPInt32Opt/lib/libsnappyHexMesh.so
#5  Foam::snappyRefineDriver::surfaceOnlyRefine(Foam::refinementParameters const&, int, int) in ~/OpenFOAM-v2312/platforms/linux64GccDPInt32Opt/lib/libsnappyHexMesh.so
#6  Foam::snappyRefineDriver::doRefine(Foam::dictionary const&, Foam::refinementParameters const&, Foam::snapParameters const&, bool, Foam::meshRefinement::FaceMergeType, Foam::dictionary const&) in ~/OpenFOAM-v2312/platforms/linux64GccDPInt32Opt/lib/libsnappyHexMesh.so
#7  ? in ~/OpenFOAM-v2312/platforms/linux64GccDPInt32Opt/bin/snappyHexMesh
#8  ? in /lib/x86_64-linux-gnu/libc.so.6
#9  __libc_start_main in /lib/x86_64-linux-gnu/libc.so.6
#10  ? in ~/OpenFOAM-v2312/platforms/linux64GccDPInt32Opt/bin/snappyHexMesh
=============
Aborted

通过报错信息生成了个obj文件，求问这个是个啥，为什么会生成

每日一捞一捞

我重新写了配置，可以snap出来了，但是不知道为什么矩形立方体被切成了三角形
请问这是什么原因

第一个图是小视角，第二个是大视角，可以看出基本上还都是小网格，没有什么变化。snappyHexMeshDict blockMeshDict
我分别运行了blockmesh和snappyhexmesh但得到了如下的记过，不管是从最终的结果可视化还是报告，好像都是错的。尤其是“non-orthogonality > 45 degrees”很多，这是为什么。到底是什么参数控制了这个结果。
No layers to generate ...
Layer mesh : cells:1584584 faces:5627764 points:2554142
Cells per refinement level:
0 105641
1 55348
2 238190
3 627103
4 558302
Writing mesh to time 0
Wrote mesh in = 3.02 s.
Layers added in = 364.18 s.
Checking final mesh ...
Checking faces in error :
non-orthogonality > 45 degrees : 210392
faces with face pyramid volume < 1e-13 : 0
faces with face-decomposition tet quality < 1e-09 : 0
faces with concavity > 80 degrees : 0
faces with skewness > 4 (internal) or 20 (boundary) : 0
faces with interpolation weights (0..1) < 0.02 : 0
faces with volume ratio of neighbour cells < 0.01 : 0
faces with face twist < 0.02 : 3
faces with triangle twist < 0.05 : 32
faces on cells with determinant < 0.001 : 0
Finished meshing with 210427 illegal faces (concave, zero area or negative cell pyramid volume)
Finished meshing in = 1509.18 s.
End[链接文本]
snappyHexMeshDict blockMeshDict

@李东岳 找到了老师，调整了时间步也是这样的，但是我调整dict中的参数似乎没怎么变化

@Be1tazzz
可以的，但是好像我的网格还是没怎么变，可能是我网格设置的问题？

@李东岳 东岳老师，我有搜到您之前回答的一个贴子《snappyHexMesh中网格始终snap不到物体表面上》，我看他上传的图跟我这个情况有点像。帖子中，您说处理对象被当成二维处理了，需要修改blockMesh中的type（将empty进行更改，随后用blockMesh, surfaceFeatureExtract, snappyHexMesh -overwrite），这个方法我试了样子没变。帖主说在您的基础上，在paramview中显示第二个时间步，切换显示就好了，我不知道这是否对我有效，现在我还在找这个切换的按钮（因为我是最近才上手这个，所以搜了半天也没找到这个）
除了这个问题，还有一个问题，就是在生成网格结束的报告中显示我生成的网格错误很多“non-orthogonality > 45 degrees : 210392”，我的理解是基本上全错了？我有按照论坛里面的snappyHexMeshDict文件和chatgpt回答调整我的文件，但是似乎我写的存在很多问题。目前我尝试调整配置中的参数（某些参数调大或调小），但对结果的改进不大。
我的stl文件是使用“city4cfd”根据点云和建筑足迹生成的（这里生成的是mesh网格，包含了openfoam需要的边界，在triSurface中），先生成了stl，然后转为vtk，最后生成emesh（因为在使用Blockmesh的时候提示需要emesh），最后snappyHexMesh生成网格。网盘链接是我生成的模型和其他的文件。
——————————————————————————————————————————
通过百度网盘分享的文件：c4c_tst.rar
链接：https://pan.baidu.com/s/1ALcAWpd8mh38VKY9YMI1IA
提取码：8dp1
--来自百度网盘超级会员V7的分享
————————————————————————————————————————————
No layers to generate ...
Layer mesh : cells:1584584 faces:5627764 points:2554142
Cells per refinement level:
0 105641
1 55348
2 238190
3 627103
4 558302
Writing mesh to time 0
Wrote mesh in = 3.02 s.
Layers added in = 364.18 s.
Checking final mesh ...
Checking faces in error :
non-orthogonality > 45 degrees : 210392
faces with face pyramid volume < 1e-13 : 0
faces with face-decomposition tet quality < 1e-09 : 0
faces with concavity > 80 degrees : 0
faces with skewness > 4 (internal) or 20 (boundary) : 0
faces with interpolation weights (0..1) < 0.02 : 0
faces with volume ratio of neighbour cells < 0.01 : 0
faces with face twist < 0.02 : 3
faces with triangle twist < 0.05 : 32
faces on cells with determinant < 0.001 : 0
Finished meshing with 210427 illegal faces (concave, zero area or negative cell pyramid volume)
Finished meshing in = 1509.18 s.
End

@Enthusiasm 你好可以问下你在哪里调的时间步吗，我也是这种情况

求问大佬！图中的原模型是在点云中保留了地理方向的模型随后通过snappyhexmesh生成的，想问下在对城市建筑建模的时候是否要对目标区域的建筑朝向和网格建立方向相一致。目前看来方向不一致面上生成了很多错位的小体块