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Search: Posts Made By: Tobi
Forum: OpenFOAM Running, Solving & CFD July 2, 2015, 06:38
Replies: 15
Views: 270
Posted By Tobi
But your solution gets very diffusive (just as a...

But your solution gets very diffusive (just as a hint).
Maybe you can switch to a high order scheme after a few timesteps, or even after the solution is converged to improve your gradients.
Forum: OpenFOAM Pre-Processing July 1, 2015, 01:50
Replies: 3
Views: 56
Posted By Tobi
Hi, I also checked the von Mises at the...

Hi,

I also checked the von Mises at the plateHole but did not get same results. Using that
formula:


https://upload.wikimedia.org/math/6/6/6/66613de183b344ea370a669dbe4087ab.png

I get...
Forum: OpenFOAM Pre-Processing June 30, 2015, 14:55
Replies: 3
Views: 56
Posted By Tobi
Hi Philip, thanks for your replay. I already...

Hi Philip,

thanks for your replay. I already saw today, that you are using stress solver within openfoam. I will check it out tomorrow but in my case it was a 3d cylinder with a tension force.
...
Forum: OpenFOAM Pre-Processing June 30, 2015, 09:46
Replies: 3
Views: 56
Posted By Tobi
Stress Analyzes, sigmaEq and Von Mises

Hi all,

I am a bit confused at the moment. Using the solver solidDisplacementFoam and a simple test case (beam with tension; fixed pressure) leads to a sigmaEq which should be the von Mises...
Forum: OpenFOAM Running, Solving & CFD June 29, 2015, 07:55
Replies: 15
Views: 270
Posted By Tobi
Hello Max, 1900 Iterations are not really a...

Hello Max,

1900 Iterations are not really a lot of iteration. In my combustion solver I have to run something like 30.000 Iterations till I reach a steady state situation. This always depend on...
Forum: OpenFOAM Running, Solving & CFD June 29, 2015, 07:48
Replies: 5
Views: 162
Posted By Tobi
Hi, normally you should not ask "why this...

Hi,

normally you should not ask "why this happens" (:
Check your results, and then think about it. For me it seems that you choose a BC configuration that allows you to create a pressure...
Forum: OpenFOAM Running, Solving & CFD June 24, 2015, 09:02
Replies: 5
Views: 162
Posted By Tobi
Hi, Boundary Condition for U for...

Hi,

Boundary Condition for U


for the outlet you can use inletOutlet and set inletValue to zero to provide no backflow



the rest is okay
Forum: OpenFOAM Running, Solving & CFD June 23, 2015, 10:15
Replies: 35
Views: 415
Posted By Tobi
In the previous post I wanted to say that you...

In the previous post I wanted to say that you have to implement it yourself ;)
Everything is still included so I know that its not a hard task :)

So good luck and keep the community up to date.
Forum: OpenFOAM Running, Solving & CFD June 23, 2015, 08:38
Replies: 35
Views: 415
Posted By Tobi
I think it's a good start. As I mentioned, the...

I think it's a good start. As I mentioned, the time resolution is necessary to get the information path (I only read about it, because I never used sonic/supersonic flows). Normally the Pimple loop...
Forum: OpenFOAM Running, Solving & CFD June 23, 2015, 08:35
Replies: 35
Views: 415
Posted By Tobi
Thanks, I already know that, but if you want...

Thanks, I already know that, but if you want additional output you have to hard code it :)
Back to the topic,...

I am not sure if in special cases D0 and D differs if you have alpha = 1. I think...
Forum: OpenFOAM Running, Solving & CFD June 23, 2015, 06:41
Replies: 35
Views: 415
Posted By Tobi
Hi all, dear Chriss, I checked the...

Hi all, dear Chriss,

I checked the relaxation function and here is the result:

### Case 1 ###
Using the following relax dictionary:

relaxationFactors
{
fields
Forum: OpenFOAM Running, Solving & CFD June 23, 2015, 05:41
Replies: 35
Views: 415
Posted By Tobi
Hi Chriss, you are welcomed for discussion....

Hi Chriss,

you are welcomed for discussion. Also I learn always new things and repeating is very good for keeping the stuff in mind. Okay as far as you told, you get the point of relaxation, final...
Forum: OpenFOAM Running, Solving & CFD June 23, 2015, 04:40
Replies: 35
Views: 415
Posted By Tobi
So you did not get the point ;) You are using...

So you did not get the point ;)
You are using relaxation wrong, as mentioned above.
Forum: OpenFOAM Running, Solving & CFD June 23, 2015, 04:39
Replies: 35
Views: 415
Posted By Tobi
Hello Chriss, some hints to your case and...

Hello Chriss,

some hints to your case and underrelaxation:



you have to specify two relaxation factors for one variable (e.g.)


U 0.4
Forum: OpenFOAM Running, Solving & CFD June 23, 2015, 04:21
Replies: 35
Views: 415
Posted By Tobi
Hi Chriss, you made a lot of mistakes using...

Hi Chriss,

you made a lot of mistakes using underrelaxation. So I think you did not get the point in my blog ;)

I will run your simulation and give a feedback.
Forum: OpenFOAM Running, Solving & CFD June 23, 2015, 03:33
Replies: 35
Views: 415
Posted By Tobi
Dear Chriss, I checked your case but I dont...

Dear Chriss,

I checked your case but I dont get the point of your simulation because the file 0 is missing. Also you don't set any pressure or velocity BC ? For U everything is (0 0 0)... Actually...
Forum: Main CFD Forum June 15, 2015, 02:45
Replies: 4
Views: 140
Posted By Tobi
Dear all, thanks for the replays and the...

Dear all,

thanks for the replays and the feedback. The sites of grimech and the nasa polynomials I know :)

Thus you showed the NASA site, can you just clear my mind about that line:

H in...
Forum: Main CFD Forum June 13, 2015, 11:09
Replies: 4
Views: 140
Posted By Tobi
NASA Polynomials >> UNITS <<

Hi all,

I am a bit confused about the NASA Polynomials and the units they have. I am right with the following stuff:



cp -> kJ/molK
H -> kJ/mol
S -> kJ/molK
Forum: OpenFOAM Programming & Development June 8, 2015, 16:38
Replies: 496
Views: 26,781
Posted By Tobi
Well you can make a lot of mistakes with the...

Well you can make a lot of mistakes with the geometry you are using. Please make just a screenshot... amount of cells dont matter for me at the moment.

In 2.2.x und 2.3.x there is the gravity term...
Forum: OpenFOAM Programming & Development June 7, 2015, 10:00
Replies: 496
Views: 26,781
Posted By Tobi
Can you show the simulation mesh ?

Can you show the simulation mesh ?
Forum: OpenFOAM Programming & Development June 2, 2015, 12:20
Replies: 496
Views: 26,781
Posted By Tobi
This is a thread for libOpenSmoke, Check out...

This is a thread for libOpenSmoke,

Check out the openfoamwiki for hagens solver.
Forum: OpenFOAM Native Meshers: snappyHexMesh and Others June 1, 2015, 01:52
Replies: 5
Views: 278
Posted By Tobi
Well done and good to know.

Well done and good to know.
Forum: OpenFOAM Native Meshers: snappyHexMesh and Others May 29, 2015, 15:36
Replies: 5
Views: 278
Posted By Tobi
Hello yaoyina, Therefore you have to use...

Hello yaoyina,

Therefore you have to use faceZones and CellZones in sHMDict. Check out the cht tutorials. Further more you create the mesh in my case with ideasUnvToFoam. Check the script.

...
Forum: OpenFOAM Pre-Processing May 19, 2015, 08:53
Replies: 25
Views: 2,207
Posted By Tobi
Dear all, thanks for the messages for...

Dear all,

thanks for the messages for bug-reporting and extension (pull requests) I get.
The latest and I hope - bug free - version 4.0 is online. Ferdinand did a very good job and now its...
Forum: OpenFOAM Programming & Development May 18, 2015, 02:37
Replies: 496
Views: 26,781
Posted By Tobi
Its due to the fact that this equation is not...

Its due to the fact that this equation is not really a energy equation as you know it from standard functionallity. Its only a passive scalar which catches the differences between H_fuel and...
Showing results 1 to 25 of 1076

 
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