Hi, it doesn't work because a dummy point is not enough, the dummy point must be part of a dummy line, which must be part of a dummy surface.
Or you can have a look at: http://www.geuz.org/pipermail/gmsh/2008/003141.html Cheers, Dave -- David Colignon, Ph.D. Collaborateur Logistique F.R.S.-FNRS (Equipements de Calcul Intensif) ACE - Applied & Computational Electromagnetics Institut Montefiore B28 Université de Liège 4000 Liège - BELGIQUE Tél: +32 (0)4 366 37 32 Fax: +32 (0)4 366 29 10 WWW: http://www.montefiore.ulg.ac.be/personnel.php?op=detail&id=898 Agenda: http://www.google.com/calendar/embed?src=david.colignon%40gmail.com Moritz Nadler wrote: > Hallo , > > > while creating my second mesh with gmesh I ran a problem: > > I have created a mesh with > gmsh -rand 1.e-8 lightmillPeriodic.geo -2 > and this .geo file: > > //begin file > highPr = 0.000015; > midPr = 0.0002; > lowPr = 0.0006; > vLowPr = 0.001; > > Point(1) = {0,0,0,highPr}; > Point(2) = {0.25E-2,0,0,midPr}; > Point(3) = {0.5E-2,0,0,highPr}; > Point(4) = {0.5E-2,0.025E-2,0,highPr}; > Point(5) = {0.75E-2,0.025E-2,0,midPr}; > Point(6) = {2.25E-2,0.025E-2,0,midPr}; > Point(7) = {2.5E-2,0.025E-2,0,highPr}; > Point(8) = {2.5E-2,0,0,highPr}; > Point(9) = {2.75E-2,0,0,midPr}; > Point(10) = {4E-2,0,0,lowPr}; > Point(11) = {9.5E-2,0,0,vLowPr}; > Point(13) = {0,9.525E-2,0,vLowPr}; > Point(14) = {0,4.025E-2,0,lowPr}; > Point(15) = {0,2.775E-2,0,midPr}; > Point(16) = {0,2.525E-2,0,highPr}; > Point(17) = {0,2.275E-2,0,midPr}; > Point(18) = {0,0.775E-2,0,midPr}; > Point(19) = {0,0.525E-2,0,highPr}; > Point(20) = {0,0.275E-2,0,midPr}; > Point(21) = {0,0.025E-2,0,highPr}; > > // dummy point to lower the mesh density in this area (does not work) > Point(22) = {0.25E-2,0.275E-2,0,midPr}; > > 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}; > Circle(11) = {11,1,13}; > 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) = {21,1}; > > Line Loop(22) = {1,2,3,4,5,6,7,8,9,10,11,13,14,15,16,17,18,19,20,21}; > Plane Surface(23) = {22}; > // end file > > But as it is stated in the gmsh manual > "The size of the mesh elements will > then be computed by linearly interpolating these characteristic lengths on > the > initial > mesh (see Section 1.2 [Mesh], page 3). This might sometimes lead to > over-refinement > in some areas" > > it did lead to some over-refinement in areas where I do not need a high mesh > density > > so I wanted to: > "so that you may have to add “dummy” geometrical entities in the model > in order to get the desired element sizes." > > so I added a first dummy point (the point with the comment in my .geo file) > with > a lower ch. length to lower the mesh density in that area but the point is > totally ignored by the meshing routine; it is not even used as a node. > > > I hope I could explain what I want to do my question then is of course: > what to do to do it right? > > > Thanks very much and > > kind regards > > > Moritz Nadler > > _______________________________________________ > gmsh mailing list > [email protected] > http://www.geuz.org/mailman/listinfo/gmsh _______________________________________________ gmsh mailing list [email protected] http://www.geuz.org/mailman/listinfo/gmsh
