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大家好，我是一名学习fluent的新人。我最近在尝试一个二维的droplet 落下然后与地面发生形变的multiphase仿真（见下图），因为对fluent各项设置不太熟，总感觉我在速度设置的地方似乎出了点问题，希望能和大家探讨，谢谢大家！！！
a4c5049d-aea4-44d4-a7b5-c6f65b932b64-image.png

关于我速度设置的fluent 的initialization界面如下
23324ed2-5c5a-4317-bb42-7a6c8842f21c-image.png

我的预期的给droplet 一个方向向下的1米每秒的初速度。
但我并不确定自己设置的如我期望所愿。在我的case中，air为1项，水为2项，我的设置见上图，我设置了Y轴
方向-1的速度，之后进行initialize ，最后patch产生了最上面的那张云图（之前已经设置产生了一个region）。

向大家请教：我的这种设置方法达到了我的预期吗？还是其实我是给了air的一个向下的初速度而并不是设置在液滴上。
如果我的设置方法是错误的，请问应该怎么修正？
先谢谢大家了！！！

这几天在看有限体积法的书，大佬的论文、《数值传热学》和 《The FVM inCFD OpenFOAM..Matlab》都看了，逛论坛发现都在推荐《Computational Methods for Fluid Dynamics》这本；去SpringerLink一搜正好今年出了新版，网上资源好像还不多，在这里分享一下： 点击下载

@Samuel-Tu 会的

@李东岳 东岳老师，请问这个速度能不能从10-2下降到10-4或者-6？

应该研究下为什么transonic需要提升对角占优

@李东岳 回答一下自己的问题。transonic下的压力方程存在对流项，对流项不利于对角占优矩阵的产生，因此transonic的压力方程要增加方程松弛。

http://dyfluid.com/rhoSimpleFoam.html

上传一下我的snappyhexMeshDict文件，请各位老师帮忙看看```
code_text

========= | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox \\ / O peration | Website: https://openfoam.org \\ / A nd | Version: 10 \\/ M anipulation | \*---------------------------------------------------------------------------*/ FoamFile { format ascii; class dictionary; object snappyHexMeshDict; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // #includeEtc "caseDicts/mesh/generation/snappyHexMeshDict.cfg" castellatedMesh true; snap true; addLayers true; geometry { cylinder { type triSurfaceMesh; file "cylinder.stl"; } refinementBox { type searchableBox; min (0.0 0.0 0.08); max (1.2 0.2 0.22); } }; castellatedMeshControls { maxLocalCells 200000; maxGlobalCells 5000000; minRefinementCells 10; maxLoadUnbalance 0.10; nCellsBetweenLevels 6; features ( { file "cylinder.eMesh"; level 3; } ); refinementSurfaces { cylinder { level (3 3); patchInfo { type wall; } } } refinementRegions { refinementBox { mode inside; level 1; } } insidePoint (0.4 0.1 0.15); } snapControls { nSmoothPatch 3; tolerance 2.0; nSolveIter 30; nRelaxIter 5; nFeatureSnapIter 10; explicitFeatureSnap true; implicitFeatureSnap false; multiRegionFeatureSnap false; } addLayersControls { layers { "(cylinder_stl_face<stlunit=MM>|cylinder_stl_top<stlunit=MM>)" { nSurfaceLayers 10; } } relativeSizes true; expansionRatio 1.05; finalLayerThickness 0.8; minThickness 0.5; } meshQualityControls {} writeFlags ( // scalarLevels // layerSets // layerFields ); mergeTolerance 1e-6; // ************************************************************************* //

@李东岳 在 HyperMesh为STARCCM+生成面网格 中说：

感谢分享！有益于后来人

共同进步！

@chszkc 谢谢大佬！！学到啦！！！

流体的动能通过涡耗散，而空间网格最小尺寸决定了你数值计算能捕捉到的最小涡的尺寸，因此小于你网格能够捕捉的尺寸的涡，其含有的动能无法通过数值模拟耗散掉。为了解决这个问题，可以理解为增加了一个和“空间尺度”有关的人工耗散，进而对小尺度的涡进行耗散，因此叫做大涡模拟。而刻画这个小涡空间尺度的标准和你的第一层网格有关，因为其决定了小涡的最大尺寸(也就是在空间上被过滤的小涡的最大尺寸)。

网上实在搜不到
作者: J.O. Hinze (Author)
出版社: McGraw-Hill Inc.,US; 2nd Revised edition edition

ISBN: 9780070290372 出版时间: 1975-05

邮箱 yuan_neu@163.com

测试编辑

@wenke 你好，你这个问题解决了吗？我也遇到了这种问题，现在也没有解决。

reFineMesh可以加密一个方向，这个需要指定区域，你试试topoSet+refineMesh呢》

I want to keep my bike close by, so I can fix it

I want to take off (remove) the bike wheel

Allen key

It doesn't fit

Move over, scoot over, can I get passed, please

She likes more and more like me everyday

I rarely (don't often) watch TV

Why did you set the temperature to 20 degrees

Dont rush me

I want to get rid of the extra oil

I can take some, I will finish what's left

She has a loose tooth, and its goin to fall out

She is not fully awake, she is a bit groggy

She is the one who loves me the most, she loves me the most

Put on the striped onesie

Move forwards and backwards

Her ton nail is broken

This is her first time seeing it

This drink is non-alcoholic, you can have a sip

Take a big step forward

A loose thread

Lift my leg and put it down

Stick out your tongue

She is lying on her side

I did it all in one go

Do you mind if I add her to our chat?

Please comment on the sentences above

Look at the lines on your arm. You leaned against something, that left lines on your arm.

Pull the handle to open the wardrobe

She just wants to be held up one your shoulder, she just wants to be held close to your chest

I am afraid of the dark

When she is sleeping, how does she know who is beside her

She does not care about anything, she is not easily bothered by things, she has high tolerance. I have a high pain tolerance.

If someone's ideas can be easily influenced by others,

She does not want to lean back

Give yourself a round of applause

Candy wrapper

I am meshing the pataya？？？

Are u scared of mosquitoes biting you?

Do you hear me calling you?

Another spoonful

How about I weigh you?

https://codepen.io/pkra/pen/EPeKjo

@东岳 这个图是刚刚改用稳态算，迭代步数不多，迭代次数多了偏差还是挺大的

@李东岳 好的，谢谢李老师

@sibo 并行限制2核，网格限制是52万

icem网格划分导入fluent时检查失败，显示Error: interface zone 3 has two adjacent cell zones.
4f68eb65-132e-4314-b0f6-6964dc466673-image.png