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多相流的有限体积法跟单相流没什么区别啊

Openfoam中是如何算面上的应力张量的？是先算单元体心的应力张量然后插值到面上吗？还是直接根据面上的速度梯度计算？

@下里巴人 看到这个帖子想起我之前做那个流化床模拟，加了跟管子就死活不收敛了，估计和你这个一样的问题。
话说有尺度差异的时候出来的这个网格好呆……明明圆形的楞给画成多边形了。
我想起Gmsh他们组最近有个博士答辩的东西就是做curve mesh的，不知道能不能用在计算上了。。

目前是在用重叠网格进行模拟，一个结构是固体，另一个是线弹性。用的是明渠造波，初始化总是崩溃，这是为什么呢？报错代码附在下面，感谢各位大佬抽出时间回答这个问题。
Grouping and repartitioning the fluid cell zones...

14 Stored Partitions:
P Cells I-Cells Cell Ratio Faces I-Faces Face Ratio Neighbors Load
0 52115 3581 0.069 176927 7246 0.041 5 1
1 52472 4620 0.088 162295 4236 0.026 4 1
2 54617 12093 0.221 134005 7412 0.055 9 1
3 52637 6006 0.114 169686 5664 0.033 4 1
4 52807 11023 0.209 167910 5289 0.031 6 1
5 52057 3479 0.067 162444 4597 0.028 5 1
6 52745 1693 0.032 170269 3362 0.020 2 1
7 52784 13211 0.250 163205 4296 0.026 5 1
8 52259 3566 0.068 176157 7128 0.040 5 1
9 51910 1672 0.032 160241 2070 0.013 1 1
10 51748 3480 0.067 164291 5004 0.030 3 1
11 54525 9324 0.171 134306 6166 0.046 8 1
12 51710 3562 0.069 166038 5640 0.034 4 1
13 54297 9707 0.179 133333 6836 0.051 9 1

Collective Partition Statistics: Minimum Maximum Total

Cell count 51710 54617 738683
Mean cell count deviation -2.0% 3.5%
Partition boundary cell count 1672 13211 87017
Partition boundary cell count ratio 3.2% 25.0% 11.8%

Face count 133333 176927 2200909
Mean face count deviation -16.7% 10.5%
Partition boundary face count 2070 7412 40198
Partition boundary face count ratio 1.3% 5.5% 1.8%

Partition neighbor count 1 9

Partition Method Metis
Stored Partition Count 14

Overset partition statistics:
P Cells Solve-cells Dead-cells
0 52115 58811 0
1 52472 52274 66
2 54617 56753 617
3 52637 54720 391
4 52807 46085 6296
5 52057 52626 0
6 52745 55832 0
7 52784 43070 6359
8 52259 58396 0
9 51910 51910 0
10 51748 53430 0
11 54525 59651 261
12 51710 54199 0
13 54297 58997 228

Overset Partition Statistics: Minimum Maximum Total

Cell count 51710 54617 738683
Mean cell count deviation -2.0% 3.5%

Solve cell count 43070 59651 756754
Mean solve cell count deviation -20.3% 10.4%

Dead cell count 0 6359 14218
Mean dead cell count deviation -100.0% 526.1%

Partition Method Metis
Stored Partition Count 14

Done.

10422 partition interfaces of the 215044 cells aspect ratio > 5 545456 groups for partitioning (including overlaps) Merging groups across partitions: 1 99888 2 8996 3 2718 4 599 5 112 6 20 7 2 8 0 Partition 535235 groups out of 738683 cells 183 partition interfaces of the 215044 cells aspect ratio > 5

Grouping and repartitioning the solid cell zones...

14 Stored Partitions:
P Cells I-Cells Cell Ratio Faces I-Faces Face Ratio Neighbors Load
0 3081 778 0.253 163329 1521 0.009 4 1
1 3081 814 0.264 163934 1432 0.009 5 1
2 3089 845 0.274 129565 7700 0.059 11 1
3 3076 819 0.266 164712 1583 0.010 3 1
4 3080 832 0.270 164935 1464 0.009 6 1
5 3079 829 0.269 162882 1455 0.009 6 1
6 3077 1026 0.333 163326 1996 0.012 7 1
7 3089 795 0.257 165081 1535 0.009 4 1
8 3092 928 0.300 163821 1637 0.010 5 1
9 3093 884 0.286 160599 1611 0.010 5 1
10 3090 761 0.246 161874 1493 0.009 4 1
11 3075 806 0.262 127548 7289 0.057 9 1
12 3097 868 0.280 162126 1544 0.010 5 1
13 3098 319 0.103 126305 4986 0.039 6 1

Collective Partition Statistics: Minimum Maximum Total

Cell count 3075 3098 43197
Mean cell count deviation -0.3% 0.4%
Partition boundary cell count 319 1026 11304
Partition boundary cell count ratio 10.3% 33.3% 26.2%

Face count 126305 165081 2133715
Mean face count deviation -18.9% 6.0%
Partition boundary face count 1432 7700 46322
Partition boundary face count ratio 0.9% 5.9% 2.2%

Partition neighbor count 3 11

Partition Method Metis
Stored Partition Count 14

Overset partition statistics:
P Cells Solve-cells Dead-cells
0 3081 55196 0
1 3081 55355 66
2 3089 54741 617
3 3076 54989 391
4 3080 47373 6296
5 3079 55136 0
6 3077 55822 0
7 3089 46159 6359
8 3092 55351 0
9 3093 55003 0
10 3090 54838 0
11 3075 56138 261
12 3097 54807 0
13 3098 55846 228

Overset Partition Statistics: Minimum Maximum Total

Cell count 3075 3098 43197
Mean cell count deviation -0.3% 0.4%

Solve cell count 46159 56138 756754
Mean solve cell count deviation -14.6% 3.9%

Dead cell count 0 6359 14218
Mean dead cell count deviation -100.0% 526.1%

Partition Method Metis
Stored Partition Count 14

Done.

42 partition interfaces of the 1073 cells aspect ratio > 5 43150 groups for partitioning (including overlaps) Merging groups across partitions: 1 6 2 0 Partition 43147 groups out of 43197 cells *** Subcommunicators recreated (11/14)! *** 565 partition interfaces of the 1073 cells aspect ratio > 5 Migrating partitions to compute-nodes.

Node 1: Process 14244: Received signal SIGSEGV.

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Node 13: Process 4932: Received signal SIGSEGV.

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Node 5: Process 7224: Received signal SIGSEGV.

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Node 11: Process 8716: Received signal SIGSEGV.

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Node 7: Process 6588: Received signal SIGSEGV.

==============================================================================

==============================================================================

Node 8: Process 5632: Received signal SIGSEGV.

==============================================================================

==============================================================================

Node 9: Process 7040: Received signal SIGSEGV.

==============================================================================

==============================================================================

Node 10: Process 3868: Received signal SIGSEGV.

==============================================================================

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Node 6: Process 4756: Received signal SIGSEGV.

==============================================================================

==============================================================================

Node 4: Process 820: Received signal SIGSEGV.

==============================================================================

===================================================================================
= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES
= RANK 0 PID 13864 RUNNING AT DESKTOP-RDMJC80
= EXIT STATUS: -1 (ffffffff) ===================================================================================
= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES
= RANK 2 PID 12200 RUNNING AT DESKTOP-RDMJC80
= EXIT STATUS: -1 (ffffffff)

The fl process could not be started.

@cccrrryyy 感谢大佬答疑解惑，也谢谢您的分享:140:

缩小模型只能保证一个无量纲数相同，一般的流动考虑雷诺数就行，缩放会带来一些非真实的物理效应，但是计算量不够就不要讲究了

@李东岳 谢谢:threaten: :qinqin:

针对一个高度为3mm，宽度为1mm的矩形微通道，用fluent mesh 画网格后，在入口流速为0.3 0.4 m/s时，计算都可以收敛。但是当入口流速为0.5m/s时，计算收敛不了，这可能是什么原因导致的，尝试过增加网格数量也无效

如果只是查看，emacs 有个 whitespace mode。
空格、tab、换行之类的特殊字符都可以显示
vim按说应该也有，没搜到

Screenshot from 2021-05-22 15-16-48.png

@buaa_hgj 我也在做柔性变形，前辈您有什么经验可以指点一二吗？

感谢李老师的回答！我刚接触of不久，请问contour是什么边界条件吗，我找了好久没有找到，of的算例里面有类似的吗

@队长别开枪 您好，我在OF8中编译了ccm26ToFoam，想模拟波物相互作用，转化后的网格checkMesh也是ok的，转化之后的网格我放到OF v1912里面进行计算的(还没编译ccmToFoam)，但是相同的设置用OpenFOAM自带的sHM划分的网格可以计算，ccm26ToFoam转化的网格却在0.02s就突然发散了。想问一下有什么解决办法吗？:135:

请教各位：
目前有一个6自由度运动的sloshing两相流模型，通过udf文件给定运动速度。

需要测出壁面位置某些点的压强时程变化，以及某些区域的水位（波高）时程变化。请问该如何设置这些测点，使其与动网格区域一起运动。

@shrine 没关系，无关紧要这些文件

@Joker 谢谢，我改一下试试

我算358

有大佬知道是什么原因么

边界面上的

@李东岳 感谢李老师。我去学习下:140:

@evensun 哦哦这样。

燃烧如果是FPV啥的，想耦合FLUENT自带的确实有些麻烦，不如直接把FPV涉及的那些变量都自定义uds再求解。如果不是FPV就不清楚了。