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<P><FONT SIZE=2>Hi,<BR>
<BR>
I've searched through the manuals and the mailing list archives, but can't find an answer to this.<BR>
<BR>
Say I define a square domain...<BR>
<BR>
lc=0.1;<BR>
<BR>
Point(1) = {0, 0, 0, 0.1*lc}; Point(2) = {1, 0, 0, lc}; Point(3) = {0, 1, 0, lc}; Point(4) = {1, 1, 0, lc};<BR>
Line(1) = {1,2}; Line(2) = {2,4}; Line(3) = {4,3}; Line(4) = {3,1};<BR>
<BR>
Line Loop(5) = {1,2,3,4};<BR>
Plane Surface(6) = {5};<BR>
<BR>
I want to use this with a diffusion solver, with two types of boundary conditions (Dirichlet and Neumann). So I set up some Physical Entities,<BR>
<BR>
Physical Line(10) = {1,2,3};<BR>
Physical Line(11) = {4};<BR>
<BR>
Physical Surface(100) = {6};<BR>
<BR>
Say I want to have a zero Neumann condition on Physical Line 10, and a non-zero Dirichlet condition on Physical Line 11. Do I have to hard code the numerical values of these into my solver? or is there someway of attaching extra data to a Physical Line?<BR>
<BR>
I could do something like,<BR>
<BR>
<BR>
Physical Line(0.0) = {1,2,3};<BR>
Physical Line(2.5) = {4};<BR>
<BR>
but then how would I specify which condition was which?<BR>
<BR>
Also, is it possible in gmsh to have more involved conditions (non-constant values across a line, Gaussian blob initial conditions, etc)?<BR>
<BR>
Many thanks,<BR>
<BR>
Chris Stott<BR>
<BR>
Department of Mathematics<BR>
University of Surrey<BR>
United Kingdom<BR>
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