Elmer Discussion Forum

Stabilization and mixed elements are partially used to overcome the same problems. Maybe you could give some pointers to the equations you want to solve so the experts in numerical methods would have more to comment on. The AC model is consistant when convergence is reached. Hence it should have onl...

The symmetry condition is often also the natural condition sometimes also called "do nothing" condition. This is the case for Poisson type of equations, for example. Therefore there most often is no option in the GUI for this either. For Navier-Stokes you typically have to set the normal v...

The elementtypes are defined in the sif file for each solver. The initial mesh files (created in your case from .grd file) define the basic nodal elements which are used for geometry definition and as basis functions if not otherwise specified. When using mixed finite elements the element basis is s...

Dear Elmer users The Elmer documentation has recently been moved under Creative Commons Attribution-No Derivative Works 3.0 License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nd/3.0/. In practice this means that it is now perfectly ok to redistribute the pdf docume...

Hello everyone, Elmer-project has decided to switch from the mailing list "elmerdiscussion@postit.csc.fi" to a discussion forum: http://elmerfem.org/forum The mailing list "elmerdiscussion@postit.csc.fi" will remain active for a transition period: - ongoing discussion should cont...

Hi Eelis, SaveLine can plot data on boundaries as well as save data in synthethic polylines. However, SaveLine does not support computation of arc lengths. You could use the coordinate values to compute them afterwards. There is an undocumented hack to get the nodal weight resulting from standard in...

The difference between "mean" and "int mean" is that the former is a number average (\sum x_i / n) and the latter an integral mean (\int x dA / \int dA). Physically only the "int mean" makes sense. The number average is the same only when each element is of equal size. ...

There are actually a number of techniques to solve the N-S equations in Elmer. The one referred in the paper is the default. Additionally, there is an own implementation of residual free bubbless that is used often when the standard stabilization fails. The artificial compressibility (AC) in the N-S...

Hi Selim, Unfortunately, ElmerFront is no longer supported. However, it and the new ElmerGUI have the common feature that the .sif file is not the format in which the state of the graphical user interface is stored. Hence, any manual changes made in the .sif file will not be taken into account when ...

Another possibility is to use really large time-steps at the beginning which effectively make the equation steady-state. This makes it possible to have the initalization within the same simulation. However, often there is no steady-state solution and solving with long time-steps will not result into...