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d8ddb624-ae67-45a5-b91b-a37014bcda10-image.png
最近用tecplot处理fluent云图，发现在应用edge时，出现了图示裂痕，怀疑是多核计算造成的。有大佬知道怎么解决吗？我目前了解到的是用单核打开，再输出tecplot文件。不过好像也有概率问题，并且算例较大且多，每次都这样很麻烦。有比较好的方法吗？

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; // ************************************************************************* //

@allvic 是不是可以在边界层内设监测点，得到频率分布，与T-S波的频率进行相关性验证呢？

@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！

@allanZhong 2年过去了。。。是需要乘以体积。例如我刚写了个科氏力源项：

nergySource { type coded; selectionMode all; field U; codeInclude #{ #}; codeAddSup #{ Pout<< "**codeAddSup**" << endl; const volVectorField& U = eqn.psi(); vectorField& USource = eqn.source(); vector omega(0, 0, 5e-5); const DimensionedField<scalar, volMesh>& V = mesh().V(); USource += (2.0*omega)^U*V; #}; codeAddRhoSup #{ Pout<< "**codeAddRhoSup**" << endl; #}; codeAddAlphaRhoSup #{ Pout<< "**codeAddAlphaRhoSup**" << endl; #}; }

1.我猜是symmetry这个边界条件，试一下改成wall，然后在0文件夹里自己定义上下的slip边界条件。openfoam会对生成的网格编号进行检查，外部软件的网格节点编号和blockMesh的逻辑不一样。
2.可能是前后的empty边界问题，你可以在starccm里生成3D网格后，重新在openfoam里extrude来生成前后empty边界
类似这样
constructFrom patch;
sourceCase "../w3-d_hc1-3";
sourcePatches (symFront);

// If construct from patch: patch to use for back (can be same as sourcePatch)
exposedPatchName symBack;

// Flip surface normals before usage. Valid only for extrude from surface or
// patch.
flipNormals false;

//- Linear extrusion in point-normal direction
extrudeModel linearNormal;

nLayers 1;

expansionRatio 1.0;

linearNormalCoeffs
{
thickness 1;
}

// Do front and back need to be merged? Usually only makes sense for 360
// degree wedges.
mergeFaces false; //true;

// Merge small edges. Fraction of bounding box.
mergeTol 0;

HTML文件，内容如下

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<span class="timeago" title="{posts.timestampISO}"></span> </small> </a> </li> <!-- IF !@last --> <li role="separator" class="divider"></li> <!-- ENDIF --> {{{end}}} <!-- IF multiplePages --> <li class="text-center"> <a href="{url}"> [[search:see-more-results, {matchCount}]] </a> </li> <!-- ENDIF multiplePages --> </ul> </div> <!-- IF isTopic --> <div class="category-list-container hidden-sm hidden-xs"></div> <!-- ENDIF isTopic --> <div class="pull-right draft-icon hidden-xs hidden-sm"></div> <div class="btn-group pull-right action-bar hidden-sm hidden-xs"> <button class="btn btn-default composer-discard" data-action="discard" tabindex="-1"><i class="fa fa-times"></i> [[topic:composer.discard]]</button> <button class="btn btn-primary composer-submit" data-action="post" tabindex="6"><i class="fa fa-check"></i> [[topic:composer.submit]]</button> </div> </div> <div class="category-tag-row"> <div class="btn-toolbar formatting-bar"> <ul class="formatting-group"> <!-- BEGIN formatting --> <!-- IF formatting.spacer --> <li class="spacer"></li> <!-- ELSE --> <!-- IF !formatting.mobile --> <li tabindex="-1" data-format="{formatting.name}" title="{formatting.title}"><i class="{formatting.className}"></i></li> <!-- ENDIF !formatting.mobile --> <!-- ENDIF formatting.spacer --> <!-- END formatting --> <!--[if gte IE 9]><!--> <!-- IF privileges.upload:post:image --> <li class="img-upload-btn hide" data-format="picture" tabindex="-1" title="[[modules:composer.upload-picture]]"> <i class="fa fa-file-image-o"></i> </li> <!-- ENDIF privileges.upload:post:image --> <!-- IF privileges.upload:post:file --> <li class="file-upload-btn hide" data-format="upload" tabindex="-1" title="[[modules:composer.upload-file]]"> <span class="fa-stack"> <i class="fa fa-file-o fa-stack-1x"></i> <i class="fa fa-arrow-up fa-stack-1x"></i> </span> </li> <!-- ENDIF privileges.upload:post:file --> <!--<![endif]--> <!-- IF allowTopicsThumbnail --> <li tabindex="-1"> <i class="fa fa-th-large topic-thumb-btn topic-thumb-toggle-btn hide" title="[[topic:composer.thumb_title]]"></i> </li> <div class="topic-thumb-container center-block hide"> <form id="thumbForm" method="post" class="topic-thumb-form form-inline" enctype="multipart/form-data"> <img class="topic-thumb-preview"></img> <div class="form-group"> <label for="topic-thumb-url">[[topic:composer.thumb_url_label]]</label> <input type="text" id="topic-thumb-url" class="form-control" placeholder="[[topic:composer.thumb_url_placeholder]]" /> </div> <div class="form-group"> <label for="topic-thumb-file">[[topic:composer.thumb_file_label]]</label> <input type="file" id="topic-thumb-file" class="form-control" /> </div> <div class="form-group topic-thumb-ctrl"> <i class="fa fa-spinner fa-spin hide topic-thumb-spinner" title="[[topic:composer.uploading]]"></i> <i class="fa fa-times topic-thumb-btn hide topic-thumb-clear-btn" title="[[topic:composer.thumb_remove]]"></i> </div> </form> </div> <!-- ENDIF allowTopicsThumbnail --> <form id="fileForm" method="post" enctype="multipart/form-data"> <!--[if gte IE 9]><!--> <input type="file" id="files" name="files[]" multiple class="gte-ie9 hide"/> <!--<![endif]--> <!--[if lt IE 9]> <input type="file" id="files" name="files[]" class="lt-ie9 hide" value="Upload"/> <![endif]--> </form> </ul> </div> </div> <div class="row write-preview-container"> <div class="write-container"> <div class="help-text"> <span class="help hidden">[[modules:composer.compose]] <i class="fa fa-question-circle"></i></span> <span class="toggle-preview hide">[[modules:composer.show_preview]]</span> </div> <div class="pull-right draft-icon hidden-md hidden-lg"></div> <textarea class="write" tabindex="4"></textarea> </div> <div class="hidden-sm hidden-xs preview-container"> <div class="help-text"> <span class="toggle-preview">[[modules:composer.hide_preview]]</span> </div> <div class="preview well"></div> </div> </div> <!-- IF isTopicOrMain --> <div class="tag-row"> <div class="tags-container"> <div class="btn-group dropup <!-- IF !tagWhitelist.length -->hidden<!-- ENDIF !tagWhitelist.length -->" component="composer/tag/dropdown"> <button class="btn btn-default dropdown-toggle" data-toggle="dropdown" type="button"> <span class="visible-sm-inline visible-md-inline visible-lg-inline"><i class="fa fa-tags"></i></span> <span class="caret"></span> </button> <ul class="dropdown-menu"> <!-- BEGIN tagWhitelist --> <li data-tag="@value"><a href="#">@value</a></li> <!-- END tagWhitelist --> </ul> </div> <input class="tags" type="text" class="form-control" placeholder="[[tags:enter_tags_here, {minimumTagLength}, {maximumTagLength}]]" tabindex="5"/> </div> </div> <!-- ENDIF isTopicOrMain --> <!-- IF isTopic --> <ul class="category-selector visible-xs visible-sm"> </ul> <!-- ENDIF isTopic --> <div class="imagedrop"><div>[[topic:composer.drag_and_drop_images]]</div></div> <div class="resizer"><div class="trigger text-center"><i class="fa"></i></div></div> </div> </div>

@XieXiaoyang 好文章，我去研究研究

@Zhy2022 好的谢谢！之后有时间看看论文再来填坑:high:

已经解决了！谢谢各位

@李东岳 可以安装了

论坛里面有没有高手遇到overset 的后处理问题：
问题描述：fluent overset 方法计算翼型表面转拟，但是在显示翼型面上切应力时，数据分布呈现锯齿状分布。
下图1是overset cell type.
9de13be5-dde7-4e34-ba97-95264d78b5b8-image.png
图2是翼型表面的切应力
5b284d9b-e3bc-45a4-b92e-d749155a96c3-image.png

@李东岳 好的，明白了，谢谢李老师

这个要是openfaom的网格，就好处理了。2亿网格确实太多了，icem我也只画过最多几百万的网格。卡的都不行。你这2亿网格太疯狂了，机器内存应该很大。

@bestucan
先谢谢老师的回复
老师说的对。。。。

谢谢老师

@李东岳 谢谢东岳老师，看了一下完美满足需求:146:

请问各位优秀的学术者，我现在已经用fluent算完了一个三维冷态的（即没进行点火燃烧）超音速燃烧仿真，现在想要去分析计算域里某一截面上燃料与空气的混合效率，但是这个 a 的值我没办法直接获取，因为这个截面上的燃料分布是不均匀的，如果用fluent里面自带的面加权平均来算的话，这个 a 的值就比实验值小很多，所以我想请教一下在fluent或者tecplot、cfd-post这样的后处理软件怎么去正确获取a的值呢？谢谢各位

混合效率.png

在breaking wave领域，这种海浪结构，会将空气卷吸并形成很多小气泡。最近提交一个稿件，审稿人推荐我们讨论一下这方面的研究。我详细看了一下，确实有点意思。

看下图，一些实验研究已经证明，这种海浪拍打过程卷吸进的气泡具有尺寸分布。见过很多文献，都是用的DNS直接模拟研究的，结果也都能证实。

但目前我想的是，能否用PBE模型，或者其他类似模型做相关的研究。

捕获.JPG

气泡直径和分布的关系
捕获.JPG

一些参考文献

Deike, L., Melville, W. K. & Popinet, S. 2016. Air entrainment and bubble statistics in breaking waves. J. Fluid Mech. 801, 91–129.
Wang, Z., Yang, J., Stern, F., 2016. High-fidelity simulations of bubble, droplet and spray formation in breaking waves. J. Fluid Mech. 792, 307–327.
G. Soligo, A. Roccon, and A. Soldati, Breakage, coalescence and size distribution of surfactant-laden droplets in turbulent flow, J. Fluid Mech. 881, 244 (2019).
Ahmed, Z., Izbassarov, D., Costa, P., Muradoglu, M., Tammisola, O. 2020. Turbulent bubbly channel flows: Effects of soluble surfactant and viscoelasticity, Computers & Fluids 212, 104717.

厉害厉害了老铁 你回国了么？

对对对，这样是对的，我之前把应变率和湍动能搞混了，谢谢李老师了！