[Gmsh] Problems with embedded crack

Ruth V. Sabariego r.sabariego at ulg.ac.be
Tue Sep 28 10:57:00 CEST 2010


  Indeed, it seems there is a problem with Lines 52 and 80.
Changing the following option in your geo file, seems to work:

Mesh.CharacteristicLengthExtendFromBoundary = 0;
// Extend computation of mesh element sizes from the boundaries into the 
surfaces/volumes

By default is set to 1.

Regards,
Ruth


On 27/09/10 15:40, olivier jamond wrote:
> Hi, thank you for helping!
>
> I have just tried your solution. It behaves better but there is still 
> some problematic cases... Here is one:
>
> Point(1) = {0.000000,0.000000,0};
> Point(2) = {80.000000,0.000000,0};
> Point(3) = {80.000000,28.000000,0};
> Point(4) = {80.000000,40.000000,0};
> Point(5) = {0.000000,40.000000,0};
> Point(6) = {0.000000,12.000000,0};
> Point(7) = {20.000000,28.000000,0};
> Point(8) = {18.730028,32.325127,0};
> Point(9) = {15.323320,35.277056,0};
> Point(10) = {10.861481,35.918572,0};
> Point(11) = {6.761114,34.045997,0};
> Point(12) = {4.324056,30.253860,0};
> Point(13) = {4.324056,25.746140,0};
> Point(14) = {6.761114,21.954003,0};
> Point(15) = {10.861481,20.081428,0};
> Point(16) = {15.323320,20.722944,0};
> Point(17) = {18.730028,23.674873,0};
> Point(18) = {76.000000,12.000000,0};
> Point(19) = {74.730028,16.325127,0};
> Point(20) = {71.323320,19.277056,0};
> Point(21) = {66.861481,19.918572,0};
> Point(22) = {62.761114,18.045997,0};
> Point(23) = {60.324056,14.253860,0};
> Point(24) = {60.324056,9.746140,0};
> Point(25) = {62.761114,5.954003,0};
> Point(26) = {66.861481,4.081428,0};
> Point(27) = {71.323320,4.722944,0};
> Point(28) = {74.730028,7.674873,0};
> Point(29) = {0.000000,12.000000,0};
> Point(30) = {4.000000,12.000000,0};
> Point(31) = {4.998921,12.046438,0};
> Point(32) = {5.976553,12.256763,0};
> Point(33) = {6.959056,12.443009,0};
> Point(34) = {7.917472,12.728383,0};
> Point(35) = {8.881660,12.993604,0};
> Point(36) = {9.847070,13.254340,0};
> Point(37) = {10.791857,13.582024,0};
> Point(38) = {11.732240,13.922143,0};
> Point(39) = {12.683953,14.229132,0};
> Point(40) = {13.637635,14.529946,0};
> Point(41) = {14.621307,14.709919,0};
> Point(42) = {15.612789,14.840166,0};
> Point(43) = {16.598456,15.008865,0};
> Point(44) = {17.595157,15.090027,0};
> Point(45) = {18.594970,15.109361,0};
> Point(46) = {19.594568,15.081007,0};
> Point(47) = {20.593809,15.042039,0};
> Point(48) = {21.587684,14.931535,0};
> Point(49) = {22.583660,14.841912,0};
> Point(50) = {23.579780,14.753904,0};
> Point(51) = {24.570180,14.615672,0};
> Point(52) = {25.556851,14.452945,0};
> Point(53) = {26.539498,14.267462,0};
> Point(54) = {27.538870,14.302900,0};
> Point(55) = {28.538787,14.315780,0};
> Point(56) = {29.538208,14.281758,0};
> Point(57) = {80.000000,28.000000,0};
> Point(58) = {76.000000,28.000000,0};
> Point(59) = {75.004838,27.901747,0};
> Point(60) = {74.022794,27.713099,0};
> Point(61) = {73.057275,27.452766,0};
> Point(62) = {72.100706,27.161260,0};
> Point(63) = {71.108506,27.036600,0};
> Point(64) = {70.143832,26.773154,0};
> Point(65) = {69.183306,26.494963,0};
> Point(66) = {68.253875,26.125967,0};
> Point(67) = {67.303473,25.814946,0};
> Point(68) = {66.338865,25.551256,0};
> Point(69) = {65.359379,25.349745,0};
> Point(70) = {64.389750,25.105165,0};
> Point(71) = {63.405932,24.925991,0};
> Point(72) = {62.419237,24.763411,0};
> Point(73) = {61.421902,24.690451,0};
> Point(74) = {60.422787,24.732517,0};
> Point(75) = {59.424031,24.782376,0};
> Point(76) = {58.441564,24.968812,0};
> Point(77) = {57.462291,25.171360,0};
> Point(78) = {56.476254,25.337884,0};
> Point(79) = {55.482089,25.445756,0};
> Point(80) = {54.482485,25.473869,0};
> Point(81) = {53.483407,25.430930,0};
> Point(82) = {52.483763,25.404241,0};
> Point(83) = {51.485758,25.467367,0};
> Point(84) = {50.487634,25.528594,0};
> Line(1) = {1,2};
> Line(2) = {2,3};
> Line(3) = {3,4};
> Line(4) = {4,5};
> Line(5) = {5,6};
> Line(6) = {6,1};
> Line(7) = {7,8};
> Line(8) = {8,9};
> Line(9) = {9,10};
> Line(10) = {10,11};
> Line(11) = {11,12};
> Line(12) = {12,13};
> Line(13) = {13,14};
> Line(14) = {14,15};
> Line(15) = {15,16};
> Line(16) = {16,17};
> Line(17) = {17,7};
> Line(18) = {18,19};
> Line(19) = {19,20};
> Line(20) = {20,21};
> Line(21) = {21,22};
> Line(22) = {22,23};
> Line(23) = {23,24};
> Line(24) = {24,25};
> Line(25) = {25,26};
> Line(26) = {26,27};
> Line(27) = {27,28};
> Line(28) = {28,18};
> Line(29) = {6,30};
> Line(30) = {30,31};
> Line(31) = {31,32};
> Line(32) = {32,33};
> Line(33) = {33,34};
> Line(34) = {34,35};
> Line(35) = {35,36};
> Line(36) = {36,37};
> Line(37) = {37,38};
> Line(38) = {38,39};
> Line(39) = {39,40};
> Line(40) = {40,41};
> Line(41) = {41,42};
> Line(42) = {42,43};
> Line(43) = {43,44};
> Line(44) = {44,45};
> Line(45) = {45,46};
> Line(46) = {46,47};
> Line(47) = {47,48};
> Line(48) = {48,49};
> Line(49) = {49,50};
> Line(50) = {50,51};
> Line(51) = {51,52};
> Line(52) = {52,53};
> Line(53) = {53,54};
> Line(54) = {54,55};
> Line(55) = {55,56};
> Line(56) = {3,58};
> Line(57) = {58,59};
> Line(58) = {59,60};
> Line(59) = {60,61};
> Line(60) = {61,62};
> Line(61) = {62,63};
> Line(62) = {63,64};
> Line(63) = {64,65};
> Line(64) = {65,66};
> Line(65) = {66,67};
> Line(66) = {67,68};
> Line(67) = {68,69};
> Line(68) = {69,70};
> Line(69) = {70,71};
> Line(70) = {71,72};
> Line(71) = {72,73};
> Line(72) = {73,74};
> Line(73) = {74,75};
> Line(74) = {75,76};
> Line(75) = {76,77};
> Line(76) = {77,78};
> Line(77) = {78,79};
> Line(78) = {79,80};
> Line(79) = {80,81};
> Line(80) = {81,82};
> Line(81) = {82,83};
> Line(82) = {83,84};
> Line Loop(83) = {1,2,3,4,5,6};
> Line Loop(84) = {7,8,9,10,11,12,13,14,15,16,17};
> Line Loop(85) = {18,19,20,21,22,23,24,25,26,27,28};
> Plane Surface(86) = {83,-84,-85};
> Line{29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82} 
> In Surface{86};
>
> Field[1]=MathEval;
> Field[1].F ="min(0.25+( 1-Exp( 
> -((x-29.5382)^2+(y-14.2818)^2)/((12.5)^2) ) )*(4.75),0.25+( 1-Exp( 
> -((x-50.4876)^2+(y-25.5286)^2)/((12.5)^2) ) )*(4.75))";
> Background Field = 1;
>
> Thank you again for your help!
>
> Olivier
>
>>    The problem is that Line(81) cuts the Surfaces of your problem.
>> You have to split in three. That is:
>> Line(81) = {40,80};
>> Line{81} In Surface{41};
>> Line(82) = {1,40};
>> Line(83) = {79,1};
>>
>> Regards,
>> Ruth
>>
>>
>> On 21/09/10 09:17, olivier jamond wrote:
>> >/  Hi,
>> />/
>> />/  I am a PhD student and I am working with evolving cracks in
>> />/  finite-elements modelization. I am dealing with a finite-elements
>> />/  patch located in the vicinity of the crack tip. Its mesh has to be
>> />/  regenerated at each step of the propagation in order to fit the 
>> crack.
>> />/  So I generate automatically a .geo files and call gmsh at each 
>> step of
>> />/  the propagation. Some time ago, I asked in this mailling list 
>> how to
>> />/  introduce cracks with gmsh. I had been advised to use the command
>> />/  "Line{x} In Surface{y}".
>> />/
>> />/  But in some cases, some elements do not respect this constraint and
>> />/  cross the line (with the 3 2D mesh algorithms), which is really
>> />/  problematic in my developments. Here is such a case:
>> />/
>> />/  Point(1) = {2.200000,5.000000,0};
>> />/  Point(2) = {2.223310,4.711260,0};
>> />/  Point(3) = {2.292634,4.429998,0};
>> />/  Point(4) = {2.406179,4.163498,0};
>> />/  Point(5) = {2.561003,3.918664,0};
>> />/  Point(6) = {2.753096,3.701836,0};
>> />/  Point(7) = {2.977483,3.518629,0};
>> />/  Point(8) = {3.228353,3.373789,0};
>> />/  Point(9) = {3.499209,3.271067,0};
>> />/  Point(10) = {3.783034,3.213124,0};
>> />/  Point(11) = {4.072479,3.201460,0};
>> />/  Point(12) = {4.360046,3.236377,0};
>> />/  Point(13) = {4.638289,3.316971,0};
>> />/  Point(14) = {4.900000,3.441154,0};
>> />/  Point(15) = {5.138402,3.605711,0};
>> />/  Point(16) = {5.347319,3.806379,0};
>> />/  Point(17) = {5.521342,4.037962,0};
>> />/  Point(18) = {5.655963,4.294460,0};
>> />/  Point(19) = {5.747695,4.569232,0};
>> />/  Point(20) = {5.794163,4.855160,0};
>> />/  Point(21) = {5.794163,5.144840,0};
>> />/  Point(22) = {5.747695,5.430768,0};
>> />/  Point(23) = {5.655963,5.705540,0};
>> />/  Point(24) = {5.521342,5.962038,0};
>> />/  Point(25) = {5.347319,6.193621,0};
>> />/  Point(26) = {5.138402,6.394289,0};
>> />/  Point(27) = {4.900000,6.558846,0};
>> />/  Point(28) = {4.638289,6.683029,0};
>> />/  Point(29) = {4.360046,6.763623,0};
>> />/  Point(30) = {4.072479,6.798540,0};
>> />/  Point(31) = {3.783034,6.786876,0};
>> />/  Point(32) = {3.499209,6.728933,0};
>> />/  Point(33) = {3.228353,6.626211,0};
>> />/  Point(34) = {2.977483,6.481371,0};
>> />/  Point(35) = {2.753096,6.298164,0};
>> />/  Point(36) = {2.561003,6.081336,0};
>> />/  Point(37) = {2.406179,5.836502,0};
>> />/  Point(38) = {2.292634,5.570002,0};
>> />/  Point(39) = {2.223310,5.288740,0};
>> />/  Line(1) = {1,2};
>> />/  Line(2) = {2,3};
>> />/  Line(3) = {3,4};
>> />/  Line(4) = {4,5};
>> />/  Line(5) = {5,6};
>> />/  Line(6) = {6,7};
>> />/  Line(7) = {7,8};
>> />/  Line(8) = {8,9};
>> />/  Line(9) = {9,10};
>> />/  Line(10) = {10,11};
>> />/  Line(11) = {11,12};
>> />/  Line(12) = {12,13};
>> />/  Line(13) = {13,14};
>> />/  Line(14) = {14,15};
>> />/  Line(15) = {15,16};
>> />/  Line(16) = {16,17};
>> />/  Line(17) = {17,18};
>> />/  Line(18) = {18,19};
>> />/  Line(19) = {19,20};
>> />/  Line(20) = {20,21};
>> />/  Line(21) = {21,22};
>> />/  Line(22) = {22,23};
>> />/  Line(23) = {23,24};
>> />/  Line(24) = {24,25};
>> />/  Line(25) = {25,26};
>> />/  Line(26) = {26,27};
>> />/  Line(27) = {27,28};
>> />/  Line(28) = {28,29};
>> />/  Line(29) = {29,30};
>> />/  Line(30) = {30,31};
>> />/  Line(31) = {31,32};
>> />/  Line(32) = {32,33};
>> />/  Line(33) = {33,34};
>> />/  Line(34) = {34,35};
>> />/  Line(35) = {35,36};
>> />/  Line(36) = {36,37};
>> />/  Line(37) = {37,38};
>> />/  Line(38) = {38,39};
>> />/  Line(39) = {39,1};
>> />/  Line Loop(40) =
>> />/  
>> {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39};
>> />/  Plane Surface(41) = {40};
>> />/  //Recombine Surface{41};
>> />/  Point(40) = {2.600000,5.000000,0};
>> />/  Point(41) = {2.618130,4.775424,0};
>> />/  Point(42) = {2.672049,4.556665,0};
>> />/  Point(43) = {2.760362,4.349388,0};
>> />/  Point(44) = {2.880780,4.158961,0};
>> />/  Point(45) = {3.030186,3.990317,0};
>> />/  Point(46) = {3.204709,3.847823,0};
>> />/  Point(47) = {3.399830,3.735169,0};
>> />/  Point(48) = {3.610496,3.655275,0};
>> />/  Point(49) = {3.831249,3.610208,0};
>> />/  Point(50) = {4.056372,3.601135,0};
>> />/  Point(51) = {4.280036,3.628293,0};
>> />/  Point(52) = {4.496447,3.690977,0};
>> />/  Point(53) = {4.700000,3.787564,0};
>> />/  Point(54) = {4.885424,3.915553,0};
>> />/  Point(55) = {5.047915,4.071628,0};
>> />/  Point(56) = {5.183266,4.251748,0};
>> />/  Point(57) = {5.287971,4.451247,0};
>> />/  Point(58) = {5.359319,4.664958,0};
>> />/  Point(59) = {5.395460,4.887347,0};
>> />/  Point(60) = {5.395460,5.112653,0};
>> />/  Point(61) = {5.359319,5.335042,0};
>> />/  Point(62) = {5.287971,5.548753,0};
>> />/  Point(63) = {5.183266,5.748252,0};
>> />/  Point(64) = {5.047915,5.928372,0};
>> />/  Point(65) = {4.885424,6.084447,0};
>> />/  Point(66) = {4.700000,6.212436,0};
>> />/  Point(67) = {4.496447,6.309023,0};
>> />/  Point(68) = {4.280036,6.371707,0};
>> />/  Point(69) = {4.056372,6.398865,0};
>> />/  Point(70) = {3.831249,6.389792,0};
>> />/  Point(71) = {3.610496,6.344725,0};
>> />/  Point(72) = {3.399830,6.264831,0};
>> />/  Point(73) = {3.204709,6.152177,0};
>> />/  Point(74) = {3.030186,6.009683,0};
>> />/  Point(75) = {2.880780,5.841039,0};
>> />/  Point(76) = {2.760362,5.650612,0};
>> />/  Point(77) = {2.672049,5.443335,0};
>> />/  Point(78) = {2.618130,5.224576,0};
>> />/  Line(42) = {40,41};
>> />/  Line(43) = {41,42};
>> />/  Line(44) = {42,43};
>> />/  Line(45) = {43,44};
>> />/  Line(46) = {44,45};
>> />/  Line(47) = {45,46};
>> />/  Line(48) = {46,47};
>> />/  Line(49) = {47,48};
>> />/  Line(50) = {48,49};
>> />/  Line(51) = {49,50};
>> />/  Line(52) = {50,51};
>> />/  Line(53) = {51,52};
>> />/  Line(54) = {52,53};
>> />/  Line(55) = {53,54};
>> />/  Line(56) = {54,55};
>> />/  Line(57) = {55,56};
>> />/  Line(58) = {56,57};
>> />/  Line(59) = {57,58};
>> />/  Line(60) = {58,59};
>> />/  Line(61) = {59,60};
>> />/  Line(62) = {60,61};
>> />/  Line(63) = {61,62};
>> />/  Line(64) = {62,63};
>> />/  Line(65) = {63,64};
>> />/  Line(66) = {64,65};
>> />/  Line(67) = {65,66};
>> />/  Line(68) = {66,67};
>> />/  Line(69) = {67,68};
>> />/  Line(70) = {68,69};
>> />/  Line(71) = {69,70};
>> />/  Line(72) = {70,71};
>> />/  Line(73) = {71,72};
>> />/  Line(74) = {72,73};
>> />/  Line(75) = {73,74};
>> />/  Line(76) = {74,75};
>> />/  Line(77) = {75,76};
>> />/  Line(78) = {76,77};
>> />/  Line(79) = {77,78};
>> />/  Line(80) = {78,40};
>> />/  
>> Line{42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80}
>> />/  In Surface{41};
>> />/  Point(79) = {-1.000000,5.000000,0};
>> />/  Point(80) = {4.000000,5.000000,0};
>> />/  Line(81) = {79,80};
>> />/  Line{81} In Surface{41};
>> />/
>> />/  Field[1]=MathEval;
>> />/  Field[1].F ="0.080000+( 1-Exp(
>> />/  -((x-4.000000)^2+(y-5.000000)^2)/((1.600000)^2) ) 
>> )*(0.400000-0.080000)";
>> />/  Background Field = 1;
>> />/
>> />/  Is there something wrong with my input file or any kind of bug 
>> (I am
>> />/  using gmsh 2.4.2) ?
>> />/
>> />/  Thanks,
>> />/
>> />/  Best regards,
>> />/
>> />/  Olivier Jamond
>> />/
>> />/  _______________________________________________
>> />/  gmsh mailing list
>> />/  gmsh at geuz.org <http://www.geuz.org/mailman/listinfo/gmsh>
>> />/  http://www.geuz.org/mailman/listinfo/gmsh
>> />/
>> /
>> -- 
>> Dr. Ir. Ruth V. Sabariego
>> University of Liege, Dept. of Electrical Engineering&   Computer 
>> Science,
>> Applied&   Computational Electromagnetics (ACE),
>> phone: +32-4-3663737 - fax: +32-4-3662910 
>> -http://ace.montefiore.ulg.ac.be/
>
>
> _______________________________________________
> gmsh mailing list
> gmsh at geuz.org
> http://www.geuz.org/mailman/listinfo/gmsh
>

-- 
Dr. Ir. Ruth V. Sabariego
University of Liege, Dept. of Electrical Engineering&  Computer Science,
Applied&  Computational Electromagnetics (ACE),
phone: +32-4-3663737 - fax: +32-4-3662910 - http://ace.montefiore.ulg.ac.be/