Elmer Discussion Forum

Hi all, I am simulating a FSI study. It runs perfect when SaveLine solver is not used. However, when I use it to extract data along a boundary it gives segmentation fault right after elasticity solver is started. I have tried this with fluid only and it works fine. But not with FSI. Please suggest. ...

Updates on previous case. When I interchange inlet and outlet boundaries i.e. inlet being the outlet and vice versa, the solutions seems quite correct (I am yet to verify with integrating variables over the surface though). The mesh attached is very coarse (because of the size limitations) but I am ...

Hello all, I am trying to carry out incompressible flow simulation through a patient-specific artery. The solution does get converged but continuity is not preserved (verified by calculating flux in paraview). The velocity along the length of pipe (artery) keeps on decreasing even though cross-secti...

Hi Anil, I am compiling using the modified (format --> FileTest.F90) modules i.e. navierstokestest.mod and materialmodelstest.mod. The navierstokestest.mod uses materialmodelstest.mod (where casson viscosity is added) The problem is when I compile I am now getting following errors, FlowSolveTest.F90...

Hi Anil, Thank you for valuable suggestions. I could now solve the issue of linking the modules with main solver. Compiling all the files at once did the trick. I will definitely put the code for casson viscosity model along with other non-Newtonian viscosity models in github repository once I work ...

Dear Anil and Peter, I understand the procedure now. I have compiled the ModifiedFlowSolve.F90 using the elmer wrapper command and also the modules using the same command (Is it correct to compile modules in the same way? It does generate the .mod file). When I run the sif file I get the following e...

Dear all, I am trying to implement a Casson viscosity model for fluid flow in an artery. The Casson fluid is non-Newtonian in nature and thus depends on the shear rate. In the material models module I created another case with string casson and compiled the materialmodels.mod file. CASE ('casson') c...

Dear Anil, Following changes helped me achieve convergence for steady state simulation. 1. Pressure outlet boundary condition over tangential velocities = 0 (it is possible that because of patient specific geometry only normal velocity approximation at the outlet might not be valid) 2. GradP Discret...

Hi Anil, Thank you for reply. I understand the roles of density and viscosity in NS equation. I am currently working on steady state simulations. I wonder why the steady state simulation is not converging. I also tried to implement transient simulation on same geometry as you asked and it resulted i...

Dear all, I am working on steady state simulations on a patient specific geometry. The non-linear NS solver diverges as soon as simulation is started. The result norm keeps on increasing by iterations and relative change is constant at 2 or 1.999... However, the solution converges when I increase th...