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-   -   Oscillatory mesh motion setup mesh flux ERROR (https://www.cfd-online.com/Forums/openfoam-solving/59485-oscillatory-mesh-motion-setup-mesh-flux-error.html)

jaswi August 21, 2007 03:32

I am struggling to set up the
 
I am struggling to set up the moving mesh case for a cube. I tried the velocityComponentLaplacian FvMotionSolver.
It works fine.

But i have problem setting up the case for velocityLaplacian FvMotion Solver. As i have understood it requires pointMotionU and cellMotionU to be
specified. I have used oscillatingVelocity PointPatchVectorField given in src/fvMotionSolver/pointPatchFields/derived/oscillatingVelocity. I have attached the
case setup. Please please take a quick look ..

With the current setup i get the following error.....

Exec : interFoam interFoam oscillatoryMotion
Date : Aug 21 2007
Time : 09:13:16
Host : taifun
PID : 26857
Root : interFoam
Case : oscillatoryMotion
Nprocs : 1
Create time

Create mesh for time = 0

Selecting dynamicFvMesh dynamicMotionSolverFvMesh
Selecting motion solver: velocityLaplacian
Selecting motion diffusion: uniform

Reading environmentalProperties
Reading field pd

Reading field gamma

Reading field U

Reading/calculating face flux field phi

Reading transportProperties

Selecting incompressible transport model Newtonian
Selecting incompressible transport model Newtonian
Calculating field g.h

Courant Number mean: 0 max: 0


--> FOAM FATAL ERROR : mesh flux field does not exists, is the mesh actually moving?

From function fvMesh::phi()
in file fvMesh/fvMeshGeometry.C at line 314.

FOAM exiting

With Best Regards
Jaswinder

http://www.cfd-online.com/OpenFOAM_D...hment_icon.gif oscillatoryMotion.tar.gz

jens_klostermann August 21, 2007 04:52

In your case there is the boun
 
In your case there is the boundaries don't move relative to each other (since you only defined one boundary), so that I think there is now mesh movement necessary.

Jens

jaswi August 21, 2007 05:00

That is not the case. I could
 
That is not the case. I could move the cube (the domain in this case) in one direction using the velocityComponentLaplacian and specifying the velocity vector in cellMotionUx and pointMotionUx. It works .......

But when i want to move the same domain with oscillatory motion it doesn't work...?????

jaswi August 21, 2007 08:13

Prof Hrovje. Please take a loo
 
Prof Hrovje. Please take a look at as you always know what to do with problems related to MesH Motion.

Once again, briefly I explain my question:

I don't understand how to setup pointMotionU and cellMotionU which are required to be specified while using velocityLaplacian fvSolver.

How can one access these fields in order to specify desired mesh motion through trig functions.

With best regards
Jaswinder

hjasak August 22, 2007 13:04

Several good ideas for you.
 
Several good ideas for you.

Firstly, if you want someone to help you, it is a good idea to spell their name right. People get easily insulted.
Secondly, in the pack you have posted, there is 1000 cells in the mesh and 15625 values in the internal field for gamma.
Thirdly, I don't know where you got the initial field from, but setFieldsDict does not seem to fit your case.
Fourthly, it is not clear to me which solver you are running on the case. interFoam runs fine; no sensible results though...

In short, a waste of time.

Hrv

jaswi August 23, 2007 04:41

Prof Hrvoje... I am extreme
 
Prof Hrvoje...

I am extremely sorry for the spelling mistake and for posting the wrong case setup.

This time i have corrected the errors and checked the case with paraFoam. It shows the right gamma field.

I have also corrected the setFields dictionary in the /system folder.

Regarding the solver, I am using interFoam with meshMotion option. Version 1.4 onwards doesn't includes the mesh motion for interFoam but i have taken clues from your development version and got it back working with the meshMotion.

The problem i am facing is related to boundary conditions. I have tried two settings. I have included both in the /0 folder.

With the first setting (/0/1st/U, /0/1st/pointMotionU and /0/1st/cellMotionU) I get the mesh motion but the gamma field doesn't changes. In this case the U has BC as fixedValue with value uniform (0 0 0);

After searching the forum, i corrected the BC for U to be movingWallVelocity with value uniform(0 0 0). but with the second setting (/0/2nd/U, /0/2nd/pointMotionU and /0/2nd/cellMotionU) I get the following error:

--> FOAM FATAL ERROR : mesh flux field does not exists, is the mesh actually moving?

From function fvMesh::phi()
in file fvMesh/fvMeshGeometry.C at line 314.

FOAM exiting
---------------

The error comes from correctPhi.H. when the following line in the code is executed:

#include "UEqn.H"

Please take a look and this time I have tried my best not to waste your time. I have emailed to you the animation for the 1st case when the mesh motion works but doesn't updates the gamma field.

Please take look.

With Best Regards
Jaswinder
http://www.cfd-online.com/OpenFOAM_D...hment_icon.gif oscillatoryMotion.zip


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