Elmer Discussion Forum

Thank you! I see the wiki is now up and running again. Great!
Yes, the transition from php5 to php7 is not as smooth as one may expect, we are also having lots of problems at our institute with this.

jordi

We have tried to access the Wiki for use of Elmer in electrochemistry simulations but it is down since the last week or so:
http://www.elmerfem.org/elmerwiki/index ... ochemistry

Anybody has news about the fate of the wiki? It is a really useful resource...

jordi

Dear Peter, I disagree. The convective flux makes sense , and it has to be zero because velocity is zero. In this very same example in ghithub, when we solve for the velocity using NS we get a zero velocity field in all the system and the same convective flux that we reported there. You can check it...

Thank you very much again Matthias, You are right, the only real issue still remaining is the convective flux. The value of the convective flux looks like the program is computing the surface area (0.005 m x 1 m) by the concentration (0.1 Kg/m3) and a velocity of 1 m/s instead of 0 (this gives the 5...

Hi, According to the test that we are doing (see https://github.com/jfaraudo/ELMER_EXAMPLES ), the units of concentration in 2D are in fact 3D, this means Kg/m3 if you use mass units. When we integrate this concentration over a 2D volume (a surface), the result is multiplied by a fictitious dimensio...

Hi Matthias, Thanks a lot!!! I corrected the github data, there was a mess with the geometry of the system. The corrected fluxes (see the github) are similar to those predicted by Fick's law, but still we have this 1% difference. What really worries me is that the value of the flux in the steady sta...

Thanks Matthias for taking your time to help us. Your answer does not solve completelly the problem, but it helps a lot. Now, the situation is as follows: 1) Your point explains the value of the total mass in the stationary state. Assuming this "extra dimension" (not described in the manua...

Sorry Peter, but many of your comments indicate that you didn't take the time to really look in detail into our comments and files. We can simply forget and move to other software, but we do really want to understand what happens and to help if possible developers and other users. The example that w...

Yes, of course we did these tests. 1.- We reproduce all reported example data (but warning: the flux data produced in the example but not shown in the elmer wiki is also unphysical!). 2.- We tried many different steps, even reducing three orders of magnitude the time step we obtain exactly the same ...

Hi, We have tried a very simple example of a very simple diffusion system (modified from an official ELMER test example) to check that ELMER correctly calculates diffusion fluxes, but we get very annoying results. The example is simply a 2D domain with an adsorbing surface at the botom and constant ...