SHM尖锐直角边界层添加

hachikoi

最近在使用OF计算环形浮体的自衰减，采用k-omega SST模型，网格基于SHM离散，但是边角处的边界层始终贴合不上，请大神支支招。

具体问题如下：

边界贴合质量：尝试通过提升stl质量（SW和犀牛加密）/增加surfaceFeatureExtractDict-includedAngle/提升snappyHexMeshDict-features和refinementSurfaces level均没能很好地将边角贴合地很好。远看质量还行，但是边角网格质量细看却很差，请问有何提升方法
基于k-omega SST计算的yplus在1000左右，首层边界层设置为1.75mm，发现是在内环面拐角处边界层未添加上，尝试好多办法均无法添加，大家有没有添加的办法

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  v2306                                 |
|   \\  /    A nd           | Website:  www.openfoam.com                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      snappyHexMeshDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

castellatedMesh true;
snap true;
addLayers true;

geometry
{
    WECMiddle.stl
    {
        type triSurfaceMesh;
        name WECMiddle; 
        regions 
        {
            OBJECT // Defined in .stl file
            {
               name WECMiddle;
            }
        }
    }

    WECMiddleWaveElevationRefineZone
    {
        type searchableBox;
        min (-17.5 -17.5 -1.25);
        max (17.5 17.5 11.25);
    }

    WECMiddleCornerRefineZone1
    {
        type searchableCone;
        point1 (0 0 -1.5);
        radius1 12.75;
        innerRadius1 7.25;
        point2 (0 0 -1);
        radius2 12.75;
        innerRadius2 7.25;
    }

    WECMiddleCornerRefineZone2
    {
        type searchableCone;
        point1 (0 0 11);
        radius1 12.75;
        innerRadius1 7.25;
        point2 (0 0 11.5);
        radius2 12.75;
        innerRadius2 7.25;
    }
};

castellatedMeshControls
{
    maxLocalCells 200000000;
    maxGlobalCells 300000000;
    minRefinementCells 20;
    nCellsBetweenLevels 3;
    maxLoadUnbalance 0.1;
    allowFreeStandingZoneFaces true;
    resolveFeatureAngle 30;
    features
    (
        {
            file "WECMiddle.eMesh";
            level 5;
        }
    );
    refinementSurfaces
    {
        WECMiddle
        {
            level (3 3); // 1.25/2/2^3 0.0781
            patchInfo
            {
                type wall;
            }
            regions
            {
                WECMiddle
                {
                    level (3 3);
                    patchInfo
                    {
                        type wall;
                    }
                }
            }
        }
    }
    refinementRegions
    {
        WECMiddleWaveElevationRefineZone
        {
            mode inside;
            levels ((2 2));
        }

        WECMiddleCornerRefineZone1
        {
            mode inside;
            levels ((4 4));
        }

        WECMiddleCornerRefineZone2
        {
            mode inside;
            levels ((4 4));
        }
    }
    locationInMesh (0 0 0); // Generate meshes outside the body
}

snapControls
{
    tolerance 2;
    implicitFeatureSnap false;
    explicitFeatureSnap true;
    multiRegionFeatureSnap true;
    detectNearSurfacesSnap true;
    nSmoothPatch 5;
    nSolveIter 300;
    nRelaxIter 8;
    nFeatureSnapIter 10;
    nSmoothInternal 5;
    nFaceSplitInterval 5;
}

addLayersControls
{
    layers
    {
        WECMiddle
        {
            nSurfaceLayers 15;
        }
    }
    relativeSizes false;
    //thickness 0.1;
    firstLayerThickness 0.00175;
    //finalLayerThickness 0.1;
    expansionRatio 1.25;
    featureAngle 360;
    slipFeatureAngle 0;
    nGrow 0;
    nBufferCellsNoExtrude 0;
    minMedialAxisAngle 90;
    maxFaceThicknessRatio 0.5;
    maxThicknessToMedialRatio 0.3;
    minThickness 1e-06;
    nLayerIter 60;
    nRelaxIter 5;
    nSmoothSurfaceNormals 10;
    nSmoothNormals 3;
    nSmoothThickness 10;
    nRelaxedIter 20;
    nMedialAxisIter 10;
}

meshQualityControls
{
    minVol 1e-20;
    minTetQuality 1e-20;
    minArea 1e-20;
    minTwist 0.05;
    minDeterminant 1e-06;
    minFaceWeight 0.02;
    minVolRatio 0.01;
    minTriangleTwist -1;
    minFlatness 0.5;
    maxNonOrtho 70;
    maxBoundarySkewness 20;
    maxInternalSkewness 4;
    maxConcave 80;
    nSmoothScale 4;
    errorReduction 0.75;
    relaxed
    {
        minVol 1e-30;
        minTetQuality 1e-30;
        minArea 1e-30;
        minTwist 0.001;
        minDeterminant 1e-06;
        minFaceWeight 1e-06;
        minVolRatio 0.01;
        minTriangleTwist -1;
        minFlatness 0.5;
        maxNonOrtho 75;
        maxBoundarySkewness 20;
        maxInternalSkewness 8;
        maxConcave 80;
        nSmoothScale 4;
        errorReduction 0.75;
    }
}

mergeTolerance 1e-08;

debug 0;


// ************************************************************************* //

首层边界层目前为1.75mm是调试很多次后得到的最小厚度，但仍然不满足要求，请问大家有没有进一步降低的方法

先谢谢各位了

hachikoi

环形浮体的边角周围做了加了处理，之前以为是过渡不均匀造成的，但改善效果不明显
浮体外半径12.5m，内半径7.5m 高度12.5m 向上提升5m做自衰减

xpqiu

meshQualityControls 部分把 relaxed 里面的质量控制参数再放宽一些。然后 nRelaxedIter 设置为 0。

hachikoi

@xpqiu 感谢大佬回复，问题已解决请问大佬有遇到过多重overset计算错误的问题吗

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SHM尖锐直角边界层添加