refineWallLayer for reaching y+<1 for low Re number turbulence model
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Hi:)
Dear foamer i have a big promlem, i want to analysis two turbulence models on 3 element airfoil, 1. high Re number e.g realizableKE ==> 30 <y+ <200 2. low Re number e.g lunderSharmaKE ==> y+ <1 i use snappyHexMesh for meshin the domain aroun the airfoil, and after finishing the analysis with realizableKE, i execute "yPlusRAS" and it told me y+ is: Time = 3400 Reading field U Reading/calculating face flux field phi Selecting incompressible transport model Newtonian Selecting RAS turbulence model realizableKE realizableKECoeffs { Cmu 0.09; A0 4; C2 1.9; sigmak 1; sigmaEps 1.2; } Patch 5 named main_solid y+ : min: 3.92116 max: 92.2824 average: 41.5749 Patch 6 named flap_solid y+ : min: 11.3159 max: 75.4566 average: 34.844 Patch 7 named slat_solid y+ : min: 17.4322 max: 61.5812 average: 43.726 and the checkMesh for RealizableKE doeasn't complain of skewness and nonOrthogonality, here it is: Create polyMesh for time = 3400 Time = 3400 Mesh stats points: 188346 internal points: 0 faces: 368558 internal faces: 182800 cells: 91461 faces per cell: 6.02834 boundary patches: 8 point zones: 0 face zones: 0 cell zones: 0 Overall number of cells of each type: hexahedra: 88316 prisms: 584 wedges: 0 pyramids: 0 tet wedges: 0 tetrahedra: 0 polyhedra: 2561 Breakdown of polyhedra by number of faces: faces number of cells 7 1953 8 603 9 3 10 2 Checking topology... Boundary definition OK. Cell to face addressing OK. Point usage OK. Upper triangular ordering OK. Face vertices OK. Number of regions: 1 (OK). Checking patch topology for multiply connected surfaces... Patch Faces Points Surface topology topAndBottom 496 996 ok (nonclosed singly connected) inlet 176 354 ok (nonclosed singly connected) outlet 176 354 ok (nonclosed singly connected) front 91461 94173 ok (nonclosed singly connected) back 91461 94173 ok (nonclosed singly connected) main_solid 1298 2596 ok (nonclosed singly connected) flap_solid 376 752 ok (nonclosed singly connected) slat_solid 314 628 ok (nonclosed singly connected) Checking geometry... Overall domain bounding box (5.84378 11.1882 0.15) (20.9289 9.3226 0.250001) Mesh (nonempty, nonwedge) directions (1 1 0) Mesh (nonempty) directions (1 1 0) ***Number of edges not aligned with or perpendicular to nonempty directions: 33 <<Writing 30 points on nonaligned edges to set nonAlignedEdges Boundary openness (4.30491e19 2.30373e20 1.93086e13) OK. Max cell openness = 2.10615e16 OK. Max aspect ratio = 6.91795 OK. Minimum face area = 4.88326e08. Maximum face area = 0.0100272. Face area magnitudes OK. Min volume = 4.88326e09. Max volume = 0.00100272. Total volume = 43.645. Cell volumes OK. Mesh nonorthogonality Max: 62.2458 average: 3.79811 Nonorthogonality check OK. Face pyramids OK. Max skewness = 2.67447 OK. Coupled point location match (average 0) OK. Failed 1 mesh checks. but when i execute refineWallLayer for reaching lower layer thickness near the wall and also lower y+ that was proper for lunderSharmaKE, the checkMesh complain skewness alot. what should i do?:(:(:( how should i yeild the low y+ with snappyhexMesh??? please guide me:( 
here it is some pics of adding layer to main element
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here it is some pics of adding layer to the leading edge of main element

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here is some pics of adding layer to another element of 3 element airfoil (slat)

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here is some pic of slat

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