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<div class="WordSection1">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I defined a background field using matheval for a cylinder; in this case the field only depends on the distance from the cylinder axis:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Field[1].F = "0.025 + (y*y+z*z)*0.05";<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The field can be seen in the attached picture.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The question is: why do I get such mesh size on the lateral surface? The radial size of the mesh looks ok, but the longitudinal size on the lateral
surface is much bigger…<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">A.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
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<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm">
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif"">Da:</span></b><span style="font-size:10.0pt;font-family:"Segoe UI","sans-serif""> gmsh [mailto:gmsh-bounces@ace20.montefiore.ulg.ac.be]
<b>Per conto di </b>Tanguy RAFFRAY<br>
<b>Inviato:</b> venerdì 14 ottobre 2016 12.09<br>
<b>A:</b> gmsh@onelab.info<br>
<b>Oggetto:</b> Re: [Gmsh] GMSH - NACA Profile, Boundary Layers and Two level of refinements<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Good morning,<o:p></o:p></p>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Well I figured out by using the extrusion tool.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">The problem is there is a superposition of my boundary layers and the rest of the mesh.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">Is it possible to make beginning the unstructured grids at the end of the boundary layers ?<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">I simplified my .geo file to only work on the boundary layers generations.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">I saw that on an other conversation : <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">// remove the volume<br>
//Delete { Volume{1}; }<br>
<br>
//extrude the boundary of the foil inwards by 0.05, with 5 layers of elements<br>
Extrude { Surface{-232, -228}; Layers{5, 0.01}; Recombine; }<br>
// NOTE : Create Boundaries outside the airfoil<br>
<br>
// create the inner volume<br>
//Surface Loop(159) = {232, 255, 242, 246, 250, 254};<br>
//Volume(160) = {159};<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">I don’t understand the goal of removing the volume and adding and new one then. And how are chosen the surfaces which are in the Surface Loop?<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Please note that I can’t create multiple box (one around the foil to create structured grids, one at the trailing edge and one outside) because I am then using other profiles which do not like that kind of meshing.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Thank you for you help and Thank you for this amazing tool which is GMSH.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Best regards,<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">——— My Geo File ——— <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">//Define Foil Coordinates (160pts)<br>
Point(1) = { 1.000000, 0.001260, 0.0000000, 0.002};<br>
Point(2) = { 0.993720, 0.002140, 0.0000000, 0.002};<br>
Point(3) = { 0.982780, 0.003650, 0.0000000, 0.002};<br>
Point(4) = { 0.969990, 0.005390, 0.0000000, 0.002};<br>
Point(5) = { 0.955670, 0.007320, 0.0000000, 0.002};<br>
Point(6) = { 0.940260, 0.009340, 0.0000000, 0.002};<br>
Point(7) = { 0.924220, 0.011420, 0.0000000, 0.002};<br>
Point(8) = { 0.907840, 0.013500, 0.0000000, 0.002};<br>
Point(9) = { 0.891280, 0.015560, 0.0000000, 0.002};<br>
Point(10) = { 0.874620, 0.017590, 0.0000000, 0.002};<br>
Point(11) = { 0.857930, 0.019590, 0.0000000, 0.002};<br>
Point(12) = { 0.841200, 0.021550, 0.0000000, 0.002};<br>
Point(13) = { 0.824460, 0.023480, 0.0000000, 0.002};<br>
Point(14) = { 0.807710, 0.025370, 0.0000000, 0.002};<br>
Point(15) = { 0.790950, 0.027230, 0.0000000, 0.002};<br>
Point(16) = { 0.774190, 0.029050, 0.0000000, 0.002};<br>
Point(17) = { 0.757420, 0.030830, 0.0000000, 0.002};<br>
Point(18) = { 0.740660, 0.032570, 0.0000000, 0.002};<br>
Point(19) = { 0.723890, 0.034280, 0.0000000, 0.002};<br>
Point(20) = { 0.707120, 0.035940, 0.0000000, 0.002};<br>
Point(21) = { 0.690350, 0.037570, 0.0000000, 0.002};<br>
Point(22) = { 0.673590, 0.039160, 0.0000000, 0.002};<br>
Point(23) = { 0.656830, 0.040710, 0.0000000, 0.002};<br>
Point(24) = { 0.640080, 0.042210, 0.0000000, 0.002};<br>
Point(25) = { 0.623330, 0.043670, 0.0000000, 0.002};<br>
Point(26) = { 0.606590, 0.045090, 0.0000000, 0.002};<br>
Point(27) = { 0.589870, 0.046460, 0.0000000, 0.002};<br>
Point(28) = { 0.573150, 0.047780, 0.0000000, 0.002};<br>
Point(29) = { 0.556450, 0.049050, 0.0000000, 0.002};<br>
Point(30) = { 0.539760, 0.050270, 0.0000000, 0.002};<br>
Point(31) = { 0.523090, 0.051430, 0.0000000, 0.002};<br>
Point(32) = { 0.506440, 0.052530, 0.0000000, 0.002};<br>
Point(33) = { 0.489800, 0.053570, 0.0000000, 0.002};<br>
Point(34) = { 0.473190, 0.054550, 0.0000000, 0.002};<br>
Point(35) = { 0.456610, 0.055460, 0.0000000, 0.002};<br>
Point(36) = { 0.440040, 0.056310, 0.0000000, 0.002};<br>
Point(37) = { 0.423510, 0.057070, 0.0000000, 0.002};<br>
Point(38) = { 0.407010, 0.057760, 0.0000000, 0.002};<br>
Point(39) = { 0.390550, 0.058370, 0.0000000, 0.002};<br>
Point(40) = { 0.374120, 0.058890, 0.0000000, 0.002};<br>
Point(41) = { 0.357740, 0.059320, 0.0000000, 0.002};<br>
Point(42) = { 0.341400, 0.059650, 0.0000000, 0.002};<br>
Point(43) = { 0.325110, 0.059880, 0.0000000, 0.002};<br>
Point(44) = { 0.308880, 0.060000, 0.0000000, 0.002};<br>
Point(45) = { 0.292720, 0.060010, 0.0000000, 0.002};<br>
Point(46) = { 0.276620, 0.059890, 0.0000000, 0.002};<br>
Point(47) = { 0.260600, 0.059650, 0.0000000, 0.002};<br>
Point(48) = { 0.244670, 0.059270, 0.0000000, 0.002};<br>
Point(49) = { 0.228840, 0.058750, 0.0000000, 0.002};<br>
Point(50) = { 0.213130, 0.058070, 0.0000000, 0.002};<br>
Point(51) = { 0.197550, 0.057230, 0.0000000, 0.002};<br>
Point(52) = { 0.182140, 0.056220, 0.0000000, 0.002};<br>
Point(53) = { 0.166930, 0.055030, 0.0000000, 0.002};<br>
Point(54) = { 0.151960, 0.053650, 0.0000000, 0.002};<br>
Point(55) = { 0.137300, 0.052070, 0.0000000, 0.002};<br>
Point(56) = { 0.123030, 0.050290, 0.0000000, 0.002};<br>
Point(57) = { 0.109290, 0.048320, 0.0000000, 0.002};<br>
Point(58) = { 0.096220, 0.046180, 0.0000000, 0.002};<br>
Point(59) = { 0.083990, 0.043890, 0.0000000, 0.002};<br>
Point(60) = { 0.072780, 0.041500, 0.0000000, 0.002};<br>
Point(61) = { 0.062710, 0.039080, 0.0000000, 0.002};<br>
Point(62) = { 0.053800, 0.036670, 0.0000000, 0.002};<br>
Point(63) = { 0.046030, 0.034310, 0.0000000, 0.002};<br>
Point(64) = { 0.039290, 0.032030, 0.0000000, 0.002};<br>
Point(65) = { 0.033460, 0.029830, 0.0000000, 0.002};<br>
Point(66) = { 0.028400, 0.027710, 0.0000000, 0.002};<br>
Point(67) = { 0.023990, 0.025660, 0.0000000, 0.002};<br>
Point(68) = { 0.020130, 0.023670, 0.0000000, 0.002};<br>
Point(69) = { 0.016740, 0.021730, 0.0000000, 0.002};<br>
Point(70) = { 0.013760, 0.019820, 0.0000000, 0.002};<br>
Point(71) = { 0.011140, 0.017930, 0.0000000, 0.002};<br>
Point(72) = { 0.008830, 0.016060, 0.0000000, 0.002};<br>
Point(73) = { 0.006820, 0.014190, 0.0000000, 0.002};<br>
Point(74) = { 0.005080, 0.012310, 0.0000000, 0.002};<br>
Point(75) = { 0.003600, 0.010410, 0.0000000, 0.002};<br>
Point(76) = { 0.002380, 0.008510, 0.0000000, 0.002};<br>
Point(77) = { 0.001410, 0.006590, 0.0000000, 0.002};<br>
Point(78) = { 0.000700, 0.004670, 0.0000000, 0.002};<br>
Point(79) = { 0.000250, 0.002770, 0.0000000, 0.002};<br>
Point(80) = { 0.000030, 0.000910, 0.0000000, 0.002};<br>
Point(81) = { 0.000030, -0.000910, 0.0000000, 0.002};<br>
Point(82) = { 0.000250, -0.002770, 0.0000000, 0.002};<br>
Point(83) = { 0.000700, -0.004670, 0.0000000, 0.002};<br>
Point(84) = { 0.001410, -0.006590, 0.0000000, 0.002};<br>
Point(85) = { 0.002380, -0.008510, 0.0000000, 0.002};<br>
Point(86) = { 0.003600, -0.010410, 0.0000000, 0.002};<br>
Point(87) = { 0.005080, -0.012310, 0.0000000, 0.002};<br>
Point(88) = { 0.006820, -0.014190, 0.0000000, 0.002};<br>
Point(89) = { 0.008830, -0.016060, 0.0000000, 0.002};<br>
Point(90) = { 0.011140, -0.017930, 0.0000000, 0.002};<br>
Point(91) = { 0.013760, -0.019820, 0.0000000, 0.002};<br>
Point(92) = { 0.016740, -0.021730, 0.0000000, 0.002};<br>
Point(93) = { 0.020130, -0.023670, 0.0000000, 0.002};<br>
Point(94) = { 0.023990, -0.025660, 0.0000000, 0.002};<br>
Point(95) = { 0.028400, -0.027710, 0.0000000, 0.002};<br>
Point(96) = { 0.033460, -0.029830, 0.0000000, 0.002};<br>
Point(97) = { 0.039300, -0.032030, 0.0000000, 0.002};<br>
Point(98) = { 0.046030, -0.034310, 0.0000000, 0.002};<br>
Point(99) = { 0.053800, -0.036670, 0.0000000, 0.002};<br>
Point(100) = { 0.062710, -0.039080, 0.0000000, 0.002};<br>
Point(101) = { 0.072780, -0.041500, 0.0000000, 0.002};<br>
Point(102) = { 0.083990, -0.043890, 0.0000000, 0.002};<br>
Point(103) = { 0.096220, -0.046180, 0.0000000, 0.002};<br>
Point(104) = { 0.109290, -0.048320, 0.0000000, 0.002};<br>
Point(105) = { 0.123030, -0.050290, 0.0000000, 0.002};<br>
Point(106) = { 0.137300, -0.052070, 0.0000000, 0.002};<br>
Point(107) = { 0.151960, -0.053650, 0.0000000, 0.002};<br>
Point(108) = { 0.166930, -0.055030, 0.0000000, 0.002};<br>
Point(109) = { 0.182140, -0.056220, 0.0000000, 0.002};<br>
Point(110) = { 0.197550, -0.057230, 0.0000000, 0.002};<br>
Point(111) = { 0.213130, -0.058070, 0.0000000, 0.002};<br>
Point(112) = { 0.228840, -0.058750, 0.0000000, 0.002};<br>
Point(113) = { 0.244670, -0.059270, 0.0000000, 0.002};<br>
Point(114) = { 0.260600, -0.059650, 0.0000000, 0.002};<br>
Point(115) = { 0.276620, -0.059890, 0.0000000, 0.002};<br>
Point(116) = { 0.292720, -0.060010, 0.0000000, 0.002};<br>
Point(117) = { 0.308880, -0.060000, 0.0000000, 0.002};<br>
Point(118) = { 0.325110, -0.059880, 0.0000000, 0.002};<br>
Point(119) = { 0.341400, -0.059650, 0.0000000, 0.002};<br>
Point(120) = { 0.357740, -0.059320, 0.0000000, 0.002};<br>
Point(121) = { 0.374120, -0.058890, 0.0000000, 0.002};<br>
Point(122) = { 0.390550, -0.058370, 0.0000000, 0.002};<br>
Point(123) = { 0.407010, -0.057760, 0.0000000, 0.002};<br>
Point(124) = { 0.423510, -0.057070, 0.0000000, 0.002};<br>
Point(125) = { 0.440040, -0.056310, 0.0000000, 0.002};<br>
Point(126) = { 0.456610, -0.055460, 0.0000000, 0.002};<br>
Point(127) = { 0.473190, -0.054550, 0.0000000, 0.002};<br>
Point(128) = { 0.489800, -0.053570, 0.0000000, 0.002};<br>
Point(129) = { 0.506440, -0.052530, 0.0000000, 0.002};<br>
Point(130) = { 0.523090, -0.051430, 0.0000000, 0.002};<br>
Point(131) = { 0.539760, -0.050270, 0.0000000, 0.002};<br>
Point(132) = { 0.556450, -0.049050, 0.0000000, 0.002};<br>
Point(133) = { 0.573150, -0.047780, 0.0000000, 0.002};<br>
Point(134) = { 0.589870, -0.046460, 0.0000000, 0.002};<br>
Point(135) = { 0.606590, -0.045090, 0.0000000, 0.002};<br>
Point(136) = { 0.623330, -0.043670, 0.0000000, 0.002};<br>
Point(137) = { 0.640080, -0.042210, 0.0000000, 0.002};<br>
Point(138) = { 0.656830, -0.040710, 0.0000000, 0.002};<br>
Point(139) = { 0.673590, -0.039160, 0.0000000, 0.002};<br>
Point(140) = { 0.690350, -0.037570, 0.0000000, 0.002};<br>
Point(141) = { 0.707120, -0.035940, 0.0000000, 0.002};<br>
Point(142) = { 0.723890, -0.034280, 0.0000000, 0.002};<br>
Point(143) = { 0.740660, -0.032570, 0.0000000, 0.002};<br>
Point(144) = { 0.757420, -0.030830, 0.0000000, 0.002};<br>
Point(145) = { 0.774190, -0.029050, 0.0000000, 0.002};<br>
Point(146) = { 0.790950, -0.027230, 0.0000000, 0.002};<br>
Point(147) = { 0.807710, -0.025370, 0.0000000, 0.002};<br>
Point(148) = { 0.824460, -0.023480, 0.0000000, 0.002};<br>
Point(149) = { 0.841200, -0.021550, 0.0000000, 0.002};<br>
Point(150) = { 0.857930, -0.019590, 0.0000000, 0.002};<br>
Point(151) = { 0.874620, -0.017590, 0.0000000, 0.002};<br>
Point(152) = { 0.891280, -0.015560, 0.0000000, 0.002};<br>
Point(153) = { 0.907840, -0.013500, 0.0000000, 0.002};<br>
Point(154) = { 0.924220, -0.011420, 0.0000000, 0.002};<br>
Point(155) = { 0.940260, -0.009340, 0.0000000, 0.002};<br>
Point(156) = { 0.955670, -0.007320, 0.0000000, 0.002};<br>
Point(157) = { 0.969990, -0.005390, 0.0000000, 0.002};<br>
Point(158) = { 0.982780, -0.003650, 0.0000000, 0.002};<br>
Point(159) = { 0.993720, -0.002140, 0.0000000, 0.002};<br>
Point(160) = { 1.000000, -0.001260, 0.0000000, 0.002};<br>
<br>
//Define bounding box corners<br>
Point(1001) = { 6.000000, 3.000000, 0.0000000, 1.0};<br>
Point(1002) = { 6.000000, -3.000000, 0.0000000, 1.0};<br>
Point(1003) = { -3.000000, -3.000000, 0.0000000, 1.0};<br>
Point(1004) = { -3.000000, 3.000000, 0.0000000, 1.0};<br>
<br>
//Define bounding box edges<br>
Line(1) = {1001, 1002};<br>
Line(2) = {1002, 1003};<br>
Line(3) = {1003, 1004};<br>
Line(4) = {1004, 1001};<br>
<br>
//Define bounding box outer boundary<br>
Line Loop(101) = {1, 2, 3, 4};<br>
<br>
//Define foil spline and trailing edge<br>
Spline(5) = {1:160};<br>
Line(6) = {160, 1};<br>
<br>
//Define foil boundary<br>
Line Loop(102) = {5, 6};<br>
<br>
//Define unstructured far field mesh zone<br>
Plane Surface(201) = {101, 102};<br>
<br>
//Extrude unstructured far field mesh<br>
Extrude {0, 0, 1} {<br>
Surface {201};<br>
Layers{1};<br>
Recombine;<br>
}<br>
<br>
// remove the volume<br>
//Delete { Volume{1}; }<br>
<br>
//extrude the boundary of the foil inwards by 0.05, with 5 layers of elements<br>
Extrude { Surface{-232, -228}; Layers{5, 0.01}; Recombine; }<br>
// NOTE : Create Boundaries outside the airfoil<br>
<br>
// create the inner volume<br>
//Surface Loop(159) = {232, 255, 242, 246, 250, 254};<br>
//Volume(160) = {159};<br>
<br>
//Define physical surfaces - numeric designations from GUI<br>
Physical Surface("back") = {201};<br>
Physical Surface("front") = {233};<br>
Physical Surface("top") = {224};<br>
Physical Surface("bottom") = {216};<br>
Physical Surface("inlet") = {220};<br>
Physical Surface("outlet") = {212};<br>
Physical Surface("foil") = {228, 232};<br>
<br>
//Define physical volumes - numeric designations from GUI<br>
Physical Volume("internal") = {1};<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<br>
<o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom:12.0pt"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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