CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM

Problem in running coarse mesh(on the other hand fine mesh is running)

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 12, 2017, 05:19
Default Problem in running coarse mesh(on the other hand fine mesh is running)
  #1
Member
 
Ashok
Join Date: Feb 2017
Posts: 31
Rep Power: 9
ashokmoravaneni is on a distinguished road
Good Morning,

Recently I encountered a Problem. I have created 2 different cases with only difference in mesh(one is fine mesh and other is coarse), the rest of settings are undisturbed. Inspite of all the settings being same except mesh, coarse mesh case is not running but fine mesh case is running successfully. The tar files are attached below for both the cases.

Someone please kindly help me to sort out were the Problem is.
Attached Files
File Type: gz case_coarse.tar.gz (5.8 KB, 2 views)
File Type: gz case_fine.tar.gz (5.8 KB, 1 views)
ashokmoravaneni is offline   Reply With Quote

Old   July 12, 2017, 05:32
Default
  #2
Senior Member
 
floquation's Avatar
 
Kevin van As
Join Date: Sep 2014
Location: TU Delft, The Netherlands
Posts: 252
Rep Power: 21
floquation will become famous soon enough
Would you please specify a little more information?

What does "not running" mean?
Does that mean the case crashes at the very first timestep, or that the case hits a FPE after some time, or ...?
If such a crash does indeed happen, you should post the last ~3 timesteps of your log file.
floquation is offline   Reply With Quote

Old   July 12, 2017, 05:35
Default
  #3
Senior Member
 
Join Date: Aug 2014
Location: Germany
Posts: 292
Rep Power: 14
BlnPhoenix is on a distinguished road
You should also post checkMesh output for both meshes.
BlnPhoenix is offline   Reply With Quote

Old   July 12, 2017, 06:00
Default
  #4
Member
 
Ashok
Join Date: Feb 2017
Posts: 31
Rep Power: 9
ashokmoravaneni is on a distinguished road
Not running means, getting error like

--> FOAM FATAL ERROR:
Continuity error cannot be removed by adjusting the outflow.
Please check the velocity boundary conditions and/or run potentialFoam to initialise the outflow.
Total flux : 1e-300
Specified mass inflow : 1.6802e-20
Specified mass outflow : 1.83295e-20
Adjustable mass outflow : 0

Once after running interFoam I gets error message as above only in case of coarse mesh but fine mesh case runs fine.
ashokmoravaneni is offline   Reply With Quote

Old   July 12, 2017, 06:03
Default
  #5
Member
 
Ashok
Join Date: Feb 2017
Posts: 31
Rep Power: 9
ashokmoravaneni is on a distinguished road
checkMesh- coarse Mesh case

Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
points: 16151
faces: 46100
internal faces: 43900
cells: 15000
faces per cell: 6
boundary patches: 3
point zones: 0
face zones: 0
cell zones: 0

Overall number of cells of each type:
hexahedra: 15000
prisms: 0
wedges: 0
pyramids: 0
tet wedges: 0
tetrahedra: 0
polyhedra: 0

Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
Patch Faces Points Surface topology
bottomWall 500 521 ok (non-closed singly connected)
atmosphere 500 521 ok (non-closed singly connected)
movingWall 1200 1240 ok (non-closed singly connected)

Checking geometry...
Overall domain bounding box (-0.063 0 -0.063) (0.063 0.5 0.063)
Mesh has 3 geometric (non-empty/wedge) directions (1 1 1)
Mesh has 3 solution (non-empty) directions (1 1 1)
Boundary openness (2.35058e-17 1.72541e-16 -3.47107e-18) OK.
Max cell openness = 2.36956e-16 OK.
Max aspect ratio = 11.8005 OK.
Minimum face area = 1.07407e-05. Maximum face area = 0.000164764. Face area magnitudes OK.
Min volume = 1.79012e-07. Max volume = 6.615e-07. Total volume = 0.00620888. Cell volumes OK.
Mesh non-orthogonality Max: 31.7106 average: 6.63087
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 2.2423 OK.
Coupled point location match (average 0) OK.

Mesh OK.

End

CheckMesh- fineMesh

Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
points: 104091
faces: 304000
internal faces: 296000
cells: 100000
faces per cell: 6
boundary patches: 3
point zones: 0
face zones: 0
cell zones: 0

Overall number of cells of each type:
hexahedra: 100000
prisms: 0
wedges: 0
pyramids: 0
tet wedges: 0
tetrahedra: 0
polyhedra: 0

Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
Patch Faces Points Surface topology
bottomWall 2000 2041 ok (non-closed singly connected)
atmosphere 2000 2041 ok (non-closed singly connected)
movingWall 4000 4080 ok (non-closed singly connected)

Checking geometry...
Overall domain bounding box (-0.063 0 -0.063) (0.063 0.5 0.063)
Mesh has 3 geometric (non-empty/wedge) directions (1 1 1)
Mesh has 3 solution (non-empty) directions (1 1 1)
Boundary openness (4.71457e-17 6.07412e-16 1.49041e-17) OK.
Max cell openness = 2.41381e-16 OK.
Max aspect ratio = 15.9624 OK.
Minimum face area = 2.38208e-06. Maximum face area = 4.94674e-05. Face area magnitudes OK.
Min volume = 2.38208e-08. Max volume = 9.9225e-08. Total volume = 0.00622808. Cell volumes OK.
Mesh non-orthogonality Max: 37.9828 average: 7.25481
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 2.36114 OK.
Coupled point location match (average 0) OK.

Mesh OK.

End


In case of much more information, Im happy to share. Thank you
ashokmoravaneni is offline   Reply With Quote

Old   July 13, 2017, 04:35
Default
  #6
Member
 
Ashok
Join Date: Feb 2017
Posts: 31
Rep Power: 9
ashokmoravaneni is on a distinguished road
Quote:
Originally Posted by floquation View Post
Would you please specify a little more information?

What does "not running" mean?
Does that mean the case crashes at the very first timestep, or that the case hits a FPE after some time, or ...?
If such a crash does indeed happen, you should post the last ~3 timesteps of your log file.
Thank you for your Response. I mean the code gives an error as stated below

--> FOAM FATAL ERROR:
Continuity error cannot be removed by adjusting the outflow.
Please check the velocity boundary conditions and/or run potentialFoam to initialise the outflow.
Total flux : 1e-300
Specified mass inflow : 1.6802e-20
Specified mass outflow : 1.83295e-20
Adjustable mass outflow : 0

Once after running interFoam I gets error message as above only in case of coarse mesh but fine mesh case runs fine.
ashokmoravaneni is offline   Reply With Quote

Old   July 13, 2017, 04:36
Default
  #7
Member
 
Ashok
Join Date: Feb 2017
Posts: 31
Rep Power: 9
ashokmoravaneni is on a distinguished road
Quote:
Originally Posted by BlnPhoenix View Post
You should also post checkMesh output for both meshes.
checkMesh- coarse Mesh case

Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
points: 16151
faces: 46100
internal faces: 43900
cells: 15000
faces per cell: 6
boundary patches: 3
point zones: 0
face zones: 0
cell zones: 0

Overall number of cells of each type:
hexahedra: 15000
prisms: 0
wedges: 0
pyramids: 0
tet wedges: 0
tetrahedra: 0
polyhedra: 0

Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
Patch Faces Points Surface topology
bottomWall 500 521 ok (non-closed singly connected)
atmosphere 500 521 ok (non-closed singly connected)
movingWall 1200 1240 ok (non-closed singly connected)

Checking geometry...
Overall domain bounding box (-0.063 0 -0.063) (0.063 0.5 0.063)
Mesh has 3 geometric (non-empty/wedge) directions (1 1 1)
Mesh has 3 solution (non-empty) directions (1 1 1)
Boundary openness (2.35058e-17 1.72541e-16 -3.47107e-18) OK.
Max cell openness = 2.36956e-16 OK.
Max aspect ratio = 11.8005 OK.
Minimum face area = 1.07407e-05. Maximum face area = 0.000164764. Face area magnitudes OK.
Min volume = 1.79012e-07. Max volume = 6.615e-07. Total volume = 0.00620888. Cell volumes OK.
Mesh non-orthogonality Max: 31.7106 average: 6.63087
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 2.2423 OK.
Coupled point location match (average 0) OK.

Mesh OK.

End

CheckMesh- fineMesh

Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
points: 104091
faces: 304000
internal faces: 296000
cells: 100000
faces per cell: 6
boundary patches: 3
point zones: 0
face zones: 0
cell zones: 0

Overall number of cells of each type:
hexahedra: 100000
prisms: 0
wedges: 0
pyramids: 0
tet wedges: 0
tetrahedra: 0
polyhedra: 0

Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces...
Patch Faces Points Surface topology
bottomWall 2000 2041 ok (non-closed singly connected)
atmosphere 2000 2041 ok (non-closed singly connected)
movingWall 4000 4080 ok (non-closed singly connected)

Checking geometry...
Overall domain bounding box (-0.063 0 -0.063) (0.063 0.5 0.063)
Mesh has 3 geometric (non-empty/wedge) directions (1 1 1)
Mesh has 3 solution (non-empty) directions (1 1 1)
Boundary openness (4.71457e-17 6.07412e-16 1.49041e-17) OK.
Max cell openness = 2.41381e-16 OK.
Max aspect ratio = 15.9624 OK.
Minimum face area = 2.38208e-06. Maximum face area = 4.94674e-05. Face area magnitudes OK.
Min volume = 2.38208e-08. Max volume = 9.9225e-08. Total volume = 0.00622808. Cell volumes OK.
Mesh non-orthogonality Max: 37.9828 average: 7.25481
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 2.36114 OK.
Coupled point location match (average 0) OK.

Mesh OK.

End


In case of much more information, Im happy to share. Thank you
ashokmoravaneni is offline   Reply With Quote

Old   July 17, 2017, 05:56
Default
  #8
Member
 
Ashok
Join Date: Feb 2017
Posts: 31
Rep Power: 9
ashokmoravaneni is on a distinguished road
Hello, am still waiting for the Reply. Any sort of help is appreciated. Thanks in advance
ashokmoravaneni is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
how to set periodic boundary conditions Ganesh FLUENT 15 November 18, 2020 07:09
[Gmsh] 2D Mesh Generation Tutorial for GMSH aeroslacker OpenFOAM Meshing & Mesh Conversion 12 January 19, 2012 04:52
Statically Compiling OpenFOAM Issues herzfeldd OpenFOAM Installation 21 January 6, 2009 10:38
fluent add additional zones for the mesh file SSL FLUENT 2 January 26, 2008 12:55
unstructured vs. structured grids Frank Muldoon Main CFD Forum 1 January 5, 1999 11:09


All times are GMT -4. The time now is 10:48.