> On 12 Dec 2014, at 00:26, Bin Wen <[email protected]> wrote: > > I also have figured out that the unexpected small element size is somehow the > result of the large size of the domain I am trying to discretize. When I try > to mesh a 1x1 square, the mesh control works perfectly. However, when I > enlarge the square to 100x100, the mesh control does not perform properly. I > did set the characteristic length according to the domain size. Not sure if > there is any parameter that I should notice in order to correct this size > effect. Thanks > > 2014-12-11 10:00 GMT-06:00 Bin Wen <[email protected]>: > I have figured out how to control mesh using background fields through API. > But have another question. > > I am trying to mesh a complex shaped polygon (many edges) using triangle > elements. And I expect to have fine mesh close to the zigzag boundary but > coarse mesh in the middle of the domain. I am using the background field to > control the element size. All those methods in t10 (Attractor+Threshold, > MathEval, Box) work well on the rectangle domain that I used for test. > However, they do not give me expected results on the real shape. All methods > generate very dense mesh through out the domain (the element size in the > middle is a little bit larger than the boundary, but they are too small > comparing with what I specified). > > One reason I could guess is that the boundary of the polygon is composed of a > set of short segments. Therefore, they make the initial element small. But I > suppose that should only make the elements near the boundary to be small. I > expect the mesh in the middle of the domain to be very coarse. I have > disabled CharacteristicLengthExtendFromBoundary option. > > I really appreciated if you could shed any light on this. Many thanks. >
Set Mesh.CharacteristicLengthExtendFromBoundary=0 in your script. > Bin > > _______________________________________________ > gmsh mailing list > [email protected] > http://www.geuz.org/mailman/listinfo/gmsh -- Prof. Christophe Geuzaine University of Liege, Electrical Engineering and Computer Science http://www.montefiore.ulg.ac.be/~geuzaine _______________________________________________ gmsh mailing list [email protected] http://www.geuz.org/mailman/listinfo/gmsh
