> On 5 Aug 2020, at 10:12, t.esch...@dokom.net wrote: > > Dear all, > > trying to get acquainted with gmsh/getdp, I stumbled upon two problems that I > am not able to resolve. > > I am trying to model a simple conductive cell with two electrodes, a simple > one and a structured one. To me, the results look quite realistic so far (I > am still in the stage of checking), with two exceptions: > > The first: When I try to calculate the overall current by calling > plugin(Integrate) on views slightly above the simple electrode, I get two > different results (for the vector view -8,88 and the x-component view -39,9), > and neither is close enough to the expected value of -2x(4,94..4,99).
Be careful with brute-force integration. If you use GetDP would recommend using global quantities, which define such integrals in the "variationally correct" way: see e.g. https://gitlab.onelab.info/doc/tutorials/-/wikis/Electrostatics-with-floating-potentials > > The second: The current density field has few spiky values that I do not know > how to cure. Their position seems to be constant, the values seem to change > with the grid parameters, and it might be getdp-related. With a (scalar) potential formulation your current density is defined through the gradient, whose accuracy will depend quite strongly on the mesh quality. You can give the new "HXT" 3D algorithm a try, whose optimizer produces slightly better elements, and see if this improves things. Christophe > > Please, have a look and give me a hint on how to correct/proceed. Thank you. > > Kind regards, Thomas > > > > > > <porous_electrode.zip>_______________________________________________ > gmsh mailing list > gmsh@onelab.info > http://onelab.info/mailman/listinfo/gmsh — Prof. Christophe Geuzaine University of Liege, Electrical Engineering and Computer Science http://www.montefiore.ulg.ac.be/~geuzaine _______________________________________________ gmsh mailing list gmsh@onelab.info http://onelab.info/mailman/listinfo/gmsh
