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GMSH - Very strange effect - Mesh elements deleted when saving

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Old   June 30, 2015, 12:30
Default GMSH - Very strange effect - Mesh elements deleted when saving
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AdriÓ Salvador
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Dear All,

I'm sincerely desperated, I have the following geometry:
Quote:

// Gmsh project created on Tue Feb 24 11:10:01 2015
// nozzle end at x=0
//moltiplication coefficients
mm=1e-3;
mi=1e-6;

// Parameters: -------------------------------
d_nz=10*mi; //nozzle diameter 10 microns
d_c=1*mm; //inner diameter pressing collar and of first meshing zone
h_c=0.1*mm; //inner step pressing collar
H_c=4*mm; //ext heigh pressing collar
D_c=11.8*mm; //ext diameter pressing collar
D_ext=25*mm; //ext boundary
D_nz_sk=2*mm; //+9.5*mi; //11.6*mm; //nz-sk-distance &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&6
//-glass---------
d_sk=20*mi; //internal sk diameter
t_sk=1*mi; //glass thickness at the entrance
h_gl=0.2*mm; //ext part of microSK inside the cone &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&
h_gl_c=1*mm; //ext conical part of microSK
h_gl_int=1*mm; //int part of microSK
h_gl_chan=0.5*mi; //channel in front of the ext skimmer
d_gl=1.5*mm; //ext dia of capillary microSK
d_gl_int=1.1*mm; //int dia of capillary
h_glue=0.3*mm; //height of the glue
//----------------
d_cone=2*mm; //ext cone dia at the microSK
d_cone_int=1.5*mm; //int cone dia
D_cone=22*mm; //ext cone dia at the base
D_cone_int=21.5*mm; //int cone dia at the base
h_cone=21*mm;
h_ext=3*mm; //internal pressing ring heigh at dia 25mm !!!!!
// radii -------------------------------------------
r_nz=d_nz/2; //nozzle radius
r_c=d_c/2; //inner collar radius
R_c=D_c/2; //ext collar radius
R_ext=D_ext/2; //boundary radius
r_sk=d_sk/2; //
r_gl_int=d_gl_int/2;
r_gl=d_gl/2;
r_cone=d_cone/2;
r_cone_int=d_cone_int/2;
R_cone=D_cone/2;
R_cone_int=D_cone_int/2;
// Initial cell radius (im microm) to ensure enough particles
//In_cell=(11^0.5)*mi;
In_cell=3.316625*mi;
//lnk_y2=In_cell*(2^0.5)*mi;
// size of mesh
dens=0.02*mm;
dens_nz=r_nz/8;
dens_nz1=r_nz/2;
dens_nz2=2*r_nz;
newdens=dens_nz1*3;
dens_sk=r_sk/8;
dens_sk1=r_sk/2;
dens_sk2=2*r_sk;
dens_tsk=t_sk/5;

dens_nzsk=0.5*(dens_nz2+dens_sk2);
//links-----------------------------------
//link x------------
lnk_x1=10*d_nz-2*h_gl_chan;
lnk_x2=3*d_nz-h_gl_chan;
lnk_x3=D_nz_sk-2*h_gl_chan-r_sk;
lnk_x4=D_nz_sk+0.02*h_gl_c+t_sk+h_gl_chan;
//link y------------
lnk_y1=3*d_nz;
//lnk_y2=r_sk-3*t_sk;
//lnk_y2=In_cell*(2^0.5);
lnk_y2=In_cell*1.414214;
// Nozzle------------------------------------------

Point(1) = {0, 0, 0, dens_nz*1.5}; //origin
Point(2) = {0, r_nz, 0, dens_nz}; //nozzle boundary
Point(3) = {0, r_c, 0, dens*4};
Point(4) = {h_c, r_c, 0, dens*4};

// New points for an appropiate radial division
Point(5) = {lnk_x2,In_cell, 0,dens_nz1};
Point(6) = {lnk_x3, In_cell, 0, dens_sk1}; //on axis nozzle boundary
Point(7) = {lnk_x4, In_cell, 0, dens_sk2};
Point(8) = {D_nz_sk+h_gl_c+h_gl+h_gl_chan, In_cell, 0, dens};
//New points for a new denser area around the source
Point(9) = {0.0005, 0, 0, newdens};
Point(10) = {0.0005, lnk_y2, 0, newdens};
Point(11) = {0.0005, In_cell, 0, newdens};
//We put a point in line 17
Point(12)= {0.0005, 10*d_nz, 0, newdens};
//one in the middle
Point(13)={0.00025, 22*d_nz, 0, newdens};
//and we plan to close it at point 55, however no surface is really required

Point(14) = {D_nz_sk+h_gl_chan, r_sk+t_sk, 0, 0.5*(dens_tsk+dens_sk)*1.25};
Point(15) = {D_nz_sk, r_sk+t_sk, 0, dens_tsk*5.25};
Point(16) = {D_nz_sk, r_sk, 0, dens_tsk*5}; //nozzle boundary
Point(17) = {D_nz_sk+h_gl_chan+t_sk, r_sk, 0, dens_sk};
Point(18) = {D_nz_sk+h_gl_c+h_gl_chan+t_sk, r_gl_int, 0, dens*4};
Point(19) = {D_nz_sk+h_gl_c+h_gl+h_gl_chan, r_gl_int, 0, dens*4};
Point(20) = {0.00025+0.5*(0.00025), (22-2)*d_nz, 0, newdens};

Point(26) = {lnk_x3, 0, 0, dens_sk1}; //on axis nozzle boundary

Point(31) = {lnk_x4, 0, 0, dens_sk2};

Point(32) = {D_nz_sk+0.02*h_gl_c+t_sk+h_gl_chan, r_sk+(r_gl_int-r_sk)*0.02*h_gl_c/h_gl_c, 0, dens_sk*1.5}; //
Point(33) = {D_nz_sk+0.02*h_gl_c+h_gl_chan, r_sk+t_sk+(r_gl-r_sk-t_sk)*0.02*h_gl_c/h_gl_c, 0, dens_nzsk}; //
Point(34) = {lnk_x3, r_sk+t_sk+(r_gl-r_sk-t_sk)*0.02*h_gl_c/h_gl_c, 0, dens_nzsk}; //
Point(35) = {D_nz_sk+0.05*h_gl_c+t_sk+h_gl_chan, r_sk+(r_gl_int-r_sk)*0.05*h_gl_c/h_gl_c, 0, dens_sk*2*1.5}; //
Point(36) = {D_nz_sk+h_gl_chan+0.1*h_gl_c,r_sk+t_sk+(r_gl-r_sk-t_sk)*0.1*h_gl_c/h_gl_c, 0, dens_sk1*1.5}; //
//Point(37) = {D_nz_sk-8*h_gl_chan-r_sk, r_sk+t_sk+(r_gl-r_sk-t_sk)*8*h_gl_chan/h_gl_c, 0, dens_nzsk}; //
Point(37) = {lnk_x3, lnk_y2, 0, dens_nzsk}; //

Point(50) = {lnk_x2,0,0,dens_nz1};
Point(51) = {lnk_x2,lnk_y2,0,dens_nz1};
Point(52) = {0, lnk_y1,0,dens_nz1};
Point(53) = {lnk_x2,lnk_y1,0,dens_nz1};
Point(54) = {0.5*(lnk_x1+lnk_x3),10*d_nz,0,dens_sk1*3};
Point(55) = {0,10*d_nz,0, newdens};
Point(56) = {D_nz_sk+h_gl_chan+0.7*h_gl_c, r_sk+t_sk+(r_gl-r_sk-t_sk)*0.7*h_gl_c/h_gl_c, 0, dens_sk2*4}; //
Point(59) = {D_nz_sk+h_gl_c+h_gl+h_gl_chan, 0, 0, dens}; //sotto punto 19
Point(60) = {D_nz_sk+h_gl_c+h_gl+h_gl_chan, lnk_y2, 0, dens}; //sotto punto 19

//Point(70) = {lnk_x1,0.5*(lnk_y1+lnk_y2),dens_sk2};
//Point(80) = {D_nz_sk-6*t_sk, r_sk-3*t_sk, 0, dens_tsk}; //nozzle boundary

Point(82) = {lnk_x4, lnk_y2, 0, dens_sk1}; //
//
Line(1) = {1, 2}; //nozzle line
Line(2) = {2, 52};
Line(3) = {52, 55};
Line(4) = {55, 3};
Line(5) = {3, 4};
//------------------

Line(6) = {52, 53};
Line(7) = {51, 10}; //{51, 70, 37};
Line(8) = {6, 11};
Line(9) = {37, 82};
Line(10) = {82, 60};
Line(11) = {60, 8};
Line(12) = {59, 31};
//Line(13) = {31, 26};
Line(13) = {26, 31};
Line(14) = {26, 9}; //{26, 53, 50};
Spline(15) = {12, 20, 13, 55};

Line(16) = {50, 1};
Line(17) = {12, 54};
Line(18) = {53, 51};
Line(19) = {34, 37};
Line(20) = {34, 33};
Line(21) = {4, 56};
Line(22) = {56, 36};
Line(23) = {36, 33};
Line(24) = {33, 14};
Line(25) = {14, 15};
Line(26) = {15, 16};
Line(27) = {16, 17};
Line(28) = {17, 32};
Line(29) = {32, 35};
Line(30) = {35, 18};
Line(31) = {18, 19};
Line(32) = {19, 60};
Line(33) = {32, 82};
Line(34) = {54, 36};
Line(35) = {9, 11};
Line(36) = {11, 10};
Line(37) = {37, 10};
Line(39) = {9, 50};
Line(40) = {10, 12};
Line(47) = {50, 5};

Line(48) = {37, 6};
Line(49) = {82, 7};

Line(150) = {6, 7};
Line(151) = {7, 8};
Line(152) = {6, 26};
Line(153) = {7, 31};
Line(154) = {8, 59};
Line(155) = {11, 5};
Line(156) = {5, 51};

Line Loop(50) = {17, 34, -22, -21, -5, -4, -15};
Plane Surface(51) = {50};
Line Loop(52) = {15, -3, 6, 18, 7, 40};
Plane Surface(53) = {52};
Line Loop(54) = {35, -39,-47,155};
Plane Surface(55) = {54};
Line Loop(56) = {-17,-34,-23, 20, -19, -37, -40};
Plane Surface(57) = {56};
Line Loop(58) = {-6, -18, 156, 47, -16, -1, -2};
Plane Surface(59) = {58};

Line Loop(60) = {37, -36, -8, -48};
Plane Surface(61) = {60};
Line Loop(62) = {8, -35, -14, -152};
Plane Surface(63) = {62};
Line Loop(64) = {-20, -24, -25, -26, -27, -28, -33, 9, 19};
Plane Surface(65) = {64};
Line Loop(66) = {-9, -49, 150, 48};
Plane Surface(67) = {66};
Line Loop(68) = {-150, -153, 13, 152};
Plane Surface(69) = {68};
Line Loop(70) = {-31,-32, 10, 33, -29, -30};
Plane Surface(71) = {70};
Line Loop(72) = {-10, -11, 151, 49};
Plane Surface(73) = {72};
Line Loop(74) = {-151, -154, -12, 153};
Plane Surface(75) = {74};
Line Loop(76) = {-7, 36, -155, -156};
Plane Surface(77) = {76};

Transfinite Line{-37} = 80 Using Progression 1.015;
Transfinite Line{36} = 1 Using Bump 1.0;
Transfinite Line{-8} = 80 Using Progression 1.015;
Transfinite Line{48} = 1 Using Bump 1.0;

Transfinite Surface {61} = {11, 10, 37, 6};
Recombine Surface{61};
//Mesh.Smoothing = 100;

Transfinite Line{35} = 1 Using Bump 1.0;
Transfinite Line{-14} = 80 Using Progression 1.015;
Transfinite Line{152} = 1 Using Bump 1.0;
Transfinite Surface {63} = {9, 11, 6, 26};
Recombine Surface{63};
//Mesh.Smoothing = 100;

Transfinite Line{9} = 3 Using Progression 1.0;
Transfinite Line{49} = 1 Using Bump 1.0;
Transfinite Line{150} = 3 Using Progression 1.0;
Transfinite Line{48} = 1 Using Bump 1.0;
Transfinite Surface {67} = {6, 37, 82, 7};
Recombine Surface{67};
//Mesh.Smoothing = 100;

Transfinite Line{152} = 1 Using Bump 1.0;
Transfinite Line{13} = 3 Using Progression 1.0;
Transfinite Line{153} = 1 Using Bump 1.0;
Transfinite Surface {69} = {26, 6, 7, 31};
Recombine Surface{69};

//Mesh.Smoothing = 100;
Transfinite Line{-10} = 40 Using Progression 1.0;
Transfinite Line{151} = 40 Using Progression 1.0;
Transfinite Line{11} = 1 Using Bump 1.0;
Transfinite Surface {73} = {7, 82, 60, 8};
Recombine Surface{73};
//Mesh.Smoothing = 100;
Transfinite Line{12} = 40 Using Progression 1.0;
Transfinite Line{154} = 1 Using Bump 1.0;
Transfinite Surface {75} = {31, 7, 8, 59};
Recombine Surface{75};
//Mesh.Smoothing = 100;
Transfinite Line{-155} = 134 Using Progression 1.015;
Transfinite Line{47} = 1 Using Bump 1.0;
Transfinite Line{-39} = 134 Using Progression 1.015;
Transfinite Surface {55} = {50, 5, 11, 9};
Recombine Surface{55};
//Mesh.Smoothing = 100;
Transfinite Line{7} = 134 Using Progression 1.015;
Transfinite Line{156} = 1 Using Bump 1;
Transfinite Surface {77} = {5, 51, 10, 11};
Recombine Surface{77};
Mesh.Smoothing = 100;

//allPoints[] = Point "*" ;
//allLines[] = Line "*" ;
allSurfaces[] = Surface "*"; //allVolumes[] = Volume "*";
//allTranslines = Transfinite Line "*";

Rotate {{1, 0, 0}, {0, 0, 0}, -(Pi*5)/(2*180) } { Surface{ allSurfaces[] } ; }


Extrude {{1, 0, 0}, {0, 0, 0}, 2*(Pi*5)/(2*180) } {
Surface{ allSurfaces[] };
Layers{ 1 };
Recombine;
//QuadTriNoNewVerts RecombLaterals;
}


Physical Surface("back") = {51, 53, 59, 77, 55, 57, 61, 63, 65, 67, 69, 73, 75, 71};//14
Physical Surface("front") = { 193, 225, 311, 529, 242, 350, 333, 279, 436, 419, 397, 507, 490, 468};
Physical Surface("inlet") = {298};
Physical Surface("nz_outlet") = {180};
Physical Surface("sk_outlet") = {506, 489, 467};
Physical Surface("nz_wall") = {295, 208, 188, 184};
Physical Surface("sk_wall") = {447, 451, 455, 384, 380, 388, 392, 396, 274,176};

Physical Volume("internalField") = {5, 4, 3, 1, 2, 8, 7, 6};
Coherence Mesh;
The problem I have is the following: Once i have saved the mesh, some elements (parallel to the z direction), disappear whan I open the mesh again. (see screenshots). Thus, the mesh does not work properly in the right part of the geometry.

Does anybody have an idea why this could be?? I'm desperated
Attached Images
File Type: jpg Element.jpg (23.3 KB, 10 views)
File Type: jpg No_element_anymore.jpg (36.7 KB, 11 views)
File Type: jpg aftersaving.jpg (35.3 KB, 11 views)
File Type: jpg beforesaving.jpg (34.0 KB, 6 views)

Last edited by Araist; July 1, 2015 at 07:23.
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Old   July 7, 2015, 16:13
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AdriÓ Salvador
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Dear All,

I have found the mistake, which is in the definition of the internal volume, not all of them are included.

Yours
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Old   July 13, 2015, 11:52
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Quote:
Originally Posted by Araist View Post
Dear All,

I have found the mistake, which is in the definition of the internal volume, not all of them are included.

Yours
Hello AdriÓ,

can you please post your update *.geo file?

Best regards,

Kate
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Old   July 15, 2015, 07:03
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Quote:
Originally Posted by KateEisenhower View Post
Hello AdriÓ,

can you please post your update *.geo file?

Best regards,

Kate
Dear Kate,

You just need to change the line

Physical Volume("internalField") = {5, 4, 3, 1, 2, 8, 7, 6};

To the correct physical volume numbers.

I can't update the file because i did some modifications for that exact mesh and it's quite different. But it should be fairly simple to do
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