On Fri, May 27, 2011 at 11:30:14AM +0100, Geordie McBain wrote: > 2011/5/26 Mark Starnes <[email protected]>: > > Hi Geordie, ?thanks for the rapid reply. > > > > Your example helped a great deal. ?Thanks! > > I went on with it, attempting to define the > > field for more than one surface, using MathEval > > to set the mesh size for an initial field, then > > defined a new second field for each surface using > > Restrict (following your example). > > > > Can you tell me how to combine these field > > definitions, please? ?I tried Min, Max, MathEval > > and MinAniso types to define my last field > > (referenced as the background field) but the > > element sizes in different regions all appear the > > same. > > > > I have attached my efforts (for what they are worth). > > Hmm. I get a good result with your third option, MinAniso. Indeed I > get the similar good result with Min, but you only want to apply Min > to the three Restricted fields {4, 5, 6}, not the constant fields {1, > 2, 3}. I attach my version of your .geo file, with your third option > uncommented, and then a picture of the mesh I get with "gmsh -2 > minaniso.geo". > > Actually this is a terrible mesh, but I assume that's beside the point > at the moment.
Hi again, Geordie and more thanks for your time. I ran your geometry here and it works; I don't know why it didn't the first time. Thanks for having a look. I have two last questions, if you don't mind. First, my impression is that if all Points used to define a volume have a characteristic length smaller than that described by a field applied, the smaller characteristic length will be adopted. Can this behaviour be changed? I have an acoustic volume filling a structural shell and the points on the shell have small lengths: this results in the elements in the acoustic volume becoming small when I can get away with them being large. Second, is it possible to define a vector field? I would like to be able to define a vector field in my structure, to stretch the generated elements in one direction relative to the other. You have been of great help. Thank you. Best regards, Mark. -- Dr. Mark Starnes Senior Physicist FT Technologies Church Lane Teddington TW11 8PA web: www.fttech.co.uk DDI: 0208 614 2730 ----- End forwarded message ----- -- Dr. Mark Starnes Senior Physicist FT Technologies Church Lane Teddington TW11 8PA web: www.fttech.co.uk DDI: 0208 614 2730 FT Technologies Limited is registered in England and Wales under registered number 01603909. Its registered office is at Church Lane, Teddington, Middlesex, TW11 8PA. The information in this message is confidential and is intended only for the use of the intended recipient(s). If you are not an intended recipient, you should not disclose, use or copy this information. Please contact the sender immediately if you have received this message in error. _______________________________________________ gmsh mailing list [email protected] http://www.geuz.org/mailman/listinfo/gmsh
