Dear David, Thanks, I now have an idea about how significant the contraction stress is compared to the applied pressure.
One thing you should check is to which degree the incompressibility condition is satisfied in your solution as well as in the reference solution. Can you export J for both cases into the vtk files? BR Kostas On Tue, Oct 10, 2017 at 5:22 PM, David Danan <[email protected]> wrote: > Dear Kostas, > > as promised, please find enclosed the result of the original simulation > without the active contraction term. > Also, note that in the end (just to be sure), i had used the routine > provided by the benchmark to generate the fiber data (even in my first > email), even though i had obtained the same data on my own. > > Thanks in advance, once again, > David. > > > > 2017-10-06 23:44 GMT+02:00 David Danan <[email protected]>: > >> Dear Yves, Dear Kostas >> >> thanks for the simplification, i was looking for this notation. >> >> Sure, i had to decrease the internal pressure (15kPa to 4 kPa) to reach >> convergence in both cases with the classical newton solver (and i fear the >> continuation method might take some time, even if it converges) so, >> meanwhile if it helps, please find enclosed the solution obtained with the >> contraction term decreased by the same amount (60kPa to 16kPa) >> (Fibre_f4Ta16.vtk) and without it (Fibre_f4Ta0.vtk). >> >> Find also enclosed the simulation with the contraction term >> (Fibre_f4Ta60.vtk) where the active constrained is the same as in my first >> email, just the internal pressure was decreased. >> >> Thanks in advance, >> best regards, >> David. >> >> >> 2017-10-06 18:05 GMT+02:00 Konstantinos Poulios <[email protected]> >> : >> >>> Dear David, >>> >>> Could you also send us a result of your simulation without the active >>> contraction term, only with internal pressure? This is to estimate how >>> large is the contribution of T_a compared to the contribution of the >>> applied pressure p. >>> >>> Best regards >>> Kostas >>> >>> On Fri, Oct 6, 2017 at 3:07 PM, Yves Renard <[email protected]> >>> wrote: >>> >>>> >>>> Dear David, >>>> >>>> I do not see any mistake. You can of course simplify the expression in >>>> >>>> "T_a*((Id(3)+Grad_u)*(f@f)):Grad_Test_u" >>>> >>>> which should be faster. >>>> >>>> Yves. >>>> >>>> >>>> >>>> >>>> Le 04/10/2017 à 18:04, David Danan a écrit : >>>> >>>> Dear Getfem users, >>>> >>>> i would like to take into account the fiber direction in my model; >>>> to do so i computed the vector associated to each point of the mesh in >>>> the order given by mf.point_of_basic_dof, stored it in a vector, used an >>>> initialized fem data >>>> >>>> model.add_initialized_fem_data("fibre",mf_u,Param_fibre); >>>> >>>> and included it in the model (basically, add the component >>>> T_a*fibre*fibre^T to the second Piola-Kirchhoff tensor in the reference >>>> configuration) >>>> getfem::add_nonlinear_generic_assembly_brick(model, >>>> mim,"T_a*(Id(3)+Grad_u)*[fibre(1)*fibre(1),fibre(1)*fibre(2) >>>> ,fibre(1)*fibre(3);fibre(2)*fibre(1),fibre(2)*fibre(2),fibre >>>> (2)*fibre(3);fibre(3)*fibre(1),fibre(3)*fibre(2),fibre(3)*fi >>>> bre(3)]:Grad_Test_u"); >>>> (this is where i have some doubts) >>>> >>>> The results i obtained are qualitatively correct but a visible >>>> difference still remains between the reference solution and my own >>>> solution. >>>> >>>> It corresponds to the last problem described in this article >>>> http://rspa.royalsocietypublishing.org/content/471/2184/20150641#sec-15 >>>> the first two were already validated, so such a difference should (a >>>> priori) come from the fiber i guess. >>>> >>>> I have tried naively to interpolate the fiber data computed on a P3 >>>> mesh on the original P2 mesh but it didn't change anything. >>>> >>>> Some help will be really appreciated, i may have overlooked something. >>>> >>>> Thanks in advance, >>>> David. >>>> >>>> PS: Please, find enclosed the reference solution (deformed.vtk) and the >>>> solution obtained (Fibre.vtk) >>>> >>>> >>>> -- >>>> >>>> Yves Renard ([email protected]) tel : (33) 04.72.43.87.08 >>>> Pole de Mathematiques, INSA-Lyon fax : (33) 04.72.43.85.29 >>>> 20, rue Albert Einstein >>>> <https://maps.google.com/?q=20,+rue+Albert+Einstein&entry=gmail&source=g> >>>> 69621 Villeurbanne Cedex, FRANCE >>>> http://math.univ-lyon1.fr/~renard >>>> >>>> --------- >>>> >>>> >>> >> >
