fluent无论设置周期边界（控制质量流率），还是速度入口压力出口，都算不出湍流，结果和层流相近，是什么原因哇。

老哥 您好 我也有同样的问题 可以求教您吗

感觉 VOF＋LEE是不是没有考虑核态沸腾 所以不会有达到饱和温度之后温度下降那一块，而正是这一块才导致沸腾换热系数上升

请问有大佬知道如何在Fluent中利用UDF添加Maxwell速度滑移和温度跳跃边界条件吗

7f0a7c02-1beb-40d4-8130-9ba6e44bbb4a-image.png d45554ce-7a55-414b-a667-8ccc7afa71c1-image.png
从上至下依次为网格1，2，3。
如图，翼型不同攻角的Cl验证，使用fluent2022r1在Re=5e5, SST k-w模型进行计算，稳态使用simple求解器，在攻角为5°的情况下，网格1（单一网格）算得的cl为0.479，网格2（使用重叠网格计算）算得的cl为0.531，网格3（单一网格，在网格2的前景网格为基础上拓展）算得的cl为0.475,文献上的cl在0.459-0.483之间，上述网格的正交性都比较好,y+=1。目前遇到的问题是不知道为什么用重叠网格后升力系数会差这么大。
已使用过的方法：
①换不同的湍流模型计算，虽然结果有差异，但都在0.52-0.55区间波动
②改变计算域大小，从12c拓展到20c均无明显变化；改变前景网格区域大小，从d=5c拓展到d=20c（此时background为30c）均无明显变化
③使用不同的fluent版本（19，20，23），无明显差异
实在找不出原因，有没有大神给小菜鸟解惑_/|o

加一个界面delta函数就可以把

你看看反应速率有没有 是太低了 还是模型设置有问题

各位前辈，我在进行一个压缩理想气体的仿真，使用了fluent自带的内燃机动网格来模拟活塞的上下运动，我这个三维压缩腔模型没有进出口，边界都是壁面，这个压缩腔内含有一部分的水，并且空气并不会溶解在水中。在时间步长为10e-05时，压缩腔内的体积平均空气质量会接近不变，但当时间步长为10e-04时，压缩腔内的体积平均空气质量会大幅度降低，导致计算结果出现很大的误差。谁知道这是怎么回事吗？270c7d84-3e4a-4a3b-a0eb-f03246e0389d-8022a33ca0ae4229656cf7dfbaaf2691.png
32391c80-98f4-4a1f-ad2b-be648153e223-b2e6b74bb524d804dfbf9eb5304f1082.png
bb35fd93-e478-4c6f-9769-18e0995e0a10-9d0248f522d25c2be2fd28eb600910ec.png
596b964a-bba4-41d7-8dce-e471b145cc16-cc8a6de7ae51246153c122cd626a3b9.png

理论上以及openfoam中，是可以作为interface处理的

@疯狂记笔记的小白 您好，现在这个问题不知您是否已经解决，我目前也遇到了这个问题，但是采用周期性边界又会破坏本身的出口条件，如您已解决，期待您的指点

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。

@霜染丹枫 请问您找到原因了吗，我用了周期边界设置的固定压降，依旧是算到最后和层流一样了

@liuxiaodong les计算圆管管道流动的，尝试了很多都最后变成层流了，这是为什么呢

@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？

怎么能够对计算完的case设定单元区域，取得这个区域内自己想要的值

fluent自定义过饱和函数时应该用那个压力数据来计算？我的静压只有不到100pa，太小了

看起来没问题呢

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

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.

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

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

Node 13: Process 4932: Received signal SIGSEGV.

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

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

Node 5: Process 7224: Received signal SIGSEGV.

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

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

Node 11: Process 8716: Received signal SIGSEGV.

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

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

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.

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

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

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.

有大佬知道是什么原因么