Search found 72 matches

by Captain Slow
24 Mar 2011, 22:22
Forum: General
Topic: Units of measure?
Replies: 4
Views: 5203

Re: Units of measure?

This has been answered many times before. Elmer assumes you use a consistent set of units-IE if you input everything in SI units, your output will be in SI units.
by Captain Slow
07 Mar 2011, 21:39
Forum: ElmerSolver
Topic: Thermal Compressibiliy
Replies: 1
Views: 1862

Thermal Compressibiliy

In the Navier-Stokes exations, one of the material compressibility model options is ''Thermal'', would I be correct in assuming that this is Isothermal compressibility I.E. compressibility with constant temperature?
by Captain Slow
03 Mar 2011, 13:43
Forum: General
Topic: Elmer Tutorial 13:Compressible flow passing a step
Replies: 5
Views: 5665

Re: Elmer Tutorial 13:Compressible flow passing a step

So, I got a bit futher with this, though I must admit to feeling as though I shouldnt trust the convergence of the heat equation:
Convergence.png
Convergence.png (737.05 KiB) Viewed 5158 times
As an aside, if I set

Code: Select all

Compressibility Model = "Thermal"
what does this do?
by Captain Slow
01 Mar 2011, 16:46
Forum: General
Topic: Elmer Tutorial 13:Compressible flow passing a step
Replies: 5
Views: 5665

Re: Elmer Tutorial 13:Compressible flow passing a step

I constructed my own sif file from the instructions in the tutorial and the step.grd file I found in the distributio, albeit from the GUI section. In any case my test with a self constructed (in gmsh) step have also failed...
by Captain Slow
01 Mar 2011, 15:16
Forum: General
Topic: Elmer Tutorial 13:Compressible flow passing a step
Replies: 5
Views: 5665

Elmer Tutorial 13:Compressible flow passing a step

I am trying to re-create the results displayed in the (non-GUI) tutorial 13 using compressible Navier Stokes&the heat equation. I have followe dthe instruction in the tutorial, and used the step.grd mesh provided, but I do not get the results in the tutorial, in fact I do not get any results at ...
by Captain Slow
10 Nov 2010, 15:17
Forum: ElmerPost
Topic: How to calculate the forces due the pressure in navier-stoke
Replies: 16
Views: 23988

Re: How to calculate the forces due the pressure in navier-stoke

Apologies-I am using an old (about 1 year old) version of the models manual-hence the 33.1 rather than 36.1 in the most recent version. So, as I understand, the fluid force is computed normal to each boundary element, then when it is displayed in the user specified output file for the boundary sum o...
by Captain Slow
09 Nov 2010, 19:27
Forum: ElmerPost
Topic: How to calculate the forces due the pressure in navier-stoke
Replies: 16
Views: 23988

Re: How to calculate the forces due the pressure in navier-stoke

May I resurrect this thread.... (it seemed more apt to add my query here rather than open a new topic) I am using the fluidic force, with the boundary sum over surfaces. Now the output force is in x y and z directions, as opposed to normal (or parallel) to the surface (which is fine, one can calcula...
by Captain Slow
03 Nov 2010, 15:55
Forum: ElmerSolver
Topic: Fluidic Force solver output
Replies: 2
Views: 2492

Re: Fluidic Force solver output

Thankyou Peter, That makes sense.

I am using the ''calculate loads'' and incompressible Navier-Stokes equation, which explains why the 4th component (continuity) is about 10 orders of magnitude smaller than the other three components.
by Captain Slow
03 Nov 2010, 12:46
Forum: ElmerSolver
Topic: Fluidic Force solver output
Replies: 2
Views: 2492

Fluidic Force solver output

Greetings, There is a fai amount of information on the fluidic force solver here: http://www.elmerfem.org/forum/viewtopic.php?f=8&t=480 which has assisted me to get this solver working nicely. However, I do have one question: the solver adds an extra four columns (in 3D) to the output (.ep file)...
by Captain Slow
29 Oct 2010, 19:33
Forum: ElmerPost
Topic: Wrong (?) results
Replies: 7
Views: 8150

Re: Wrong (?) results

As to the first question, I think the answer that you're looking for is that co-ordinates 1,2 and 3 relate to x, y, and z.