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-   -   how to set periodic boundary conditions (http://www.cfd-online.com/Forums/fluent/15320-how-set-periodic-boundary-conditions.html)

Ganesh June 18, 2008 14:16

how to set periodic boundary conditions
 
I have a problem in specifying periodic boundary conditions. The model I'm using is a section of a rectangular block with holes in it. The face to be patterned was specified as symmetric boundary condition when I modeled it in Gambit. there are two such faces parallel to each other. Periodic boundary condition is not highlighted in the define panel. I will be thankful to anyone who can tell me where I made a mistake.

I also tried to change the boundary condition of these faces to interface and grid interface these two faces with periodic type. When I iterate, it say "no periodic zones adjacent to grid interface"

sa July 27, 2008 03:26

Re: how to set periodic boundary conditions
 
which software you are using.

Regards

VU_Engineer March 2, 2010 19:50

It is ok to export the mesh out of GAMBIT with symmetric BCs,
because you (can) re-define them in FLUENT.

I believe for FLUENT you set the Periodic BC to Interfaces under "Boundary Conditions"
then under "Mesh Interfaces" you select the two Interfaces and set them to Periodic

zhang.limin March 3, 2010 13:17

define in Gambit first
 
Define in Gambit first, and import into fluent

harishg March 3, 2010 21:32

When you define periodic boundary conditions in gambit, you need to link mesh the two faces/edges together. Try doing it and then export the mesh.

krunal_me00 April 8, 2010 06:18

how to do the operation of link mesh the two faces/edges together??
 
Quote:

Originally Posted by harishg (Post 248457)
When you define periodic boundary conditions in gambit, you need to link mesh the two faces/edges together. Try doing it and then export the mesh.

how to do the operation of link mesh the two faces/edges together n create periodic wall in GAMBIT???

thank you

VU_Engineer April 8, 2010 10:20

Quote:

Originally Posted by krunal_me00 (Post 253738)
how to do the operation of link mesh the two faces/edges together n create periodic wall in GAMBIT???

thank you

I've struggled with this and would really like some guidance in this area as well

Far April 9, 2010 10:20

If your problem is 3D then go to face mesh options
In 2nd row (by right clicking) you will see the link face mesh. Select the faces on both sides of periodic boundary and choose option of periodic (also select reverse direction if need be) and then set boundary contions of periodic in boundary conditon panel

hope it helps

sukanta April 28, 2011 05:18

if my problem is 2d then??
 
i have a problem with 2d savonius rotor. I am trying to create periodic zones. now i want to know how to create shadow in gambit so that when we import in the fluent we can create periodic zones and delete the shadow zone.

haihek June 13, 2011 15:09

I am simulating a moving 2-D droplet using Fluent 6.3, and i am using the translational periodic boundary condition so that when the droplet moves to the right boundary at the end of the domain it will re-appear on the left side of the domain. The problem i am facing is that when the droplet moves to the lower right side boundary, it re-appear on the upper left side boundary. So basically it translational on both X- and Y- axis.

How can i make it translational only in the X-Axis.

Thanks.

teguhtf September 4, 2011 22:55

help me pelase!!
 
Dear all,
I have problems with periodic BC too. I want to remake geometry of mixing plane. So i import the fanstage.msh into GAMBIT. I have meshed and specified the fan. but when i export to FLUENT there are errors. I don't know how to fix it. Help me please!!
thanks you so much.
Teguh
&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& &&&&&&&

Here is the *.jou file
/ Journal File for GAMBIT 2.4.6, Database 2.4.4, ntx86 SP2007051421
/ Identifier "bismillah fan"
/ File opened for write Sun Sep 04 17:07:14 2011.
face create radius 0.103 xyplane circle
face create radius 0.14 xyplane circle
face subtract "face.2" faces "face.1"
window modify shade
vertex create coordinates 0 0 0
edge create straight "vertex.4" "vertex.2"
edge cmove "edge.4" multiple 1 dangle 40 vector 0 0 1 origin 0 0 0
face split "face.2" edges "edge.4"
face split "face.2" edges "edge.5"
window modify shade
face delete "face.2" lowertopology
save
volume create translate "face.3" vector 0 0 -0.1165
window modify shade
vertex create coordinates 0 0 0
vertex cmove "vertex.13" multiple 1 offset 0 0 -1.5
face create radius 0.14 xyplane circle
undo
/Undone to: face create radius 0.14 xyplane circle
vertex cmove "vertex.14" multiple 1 offset 0.1 0 0
vertex cmove "vertex.14" multiple 1 offset 0 0.1 0
coordinate create cartesian vertices "vertex.14" "vertex.15" "vertex.16"
face create radius 0.14 xyplane circle
face create radius 0.103 xyplane circle
face subtract "face.9" faces "face.10"
window modify shade
edge create straight "vertex.19" "vertex.17"
edge summarize "edge.21"
edge delete "edge.18" "edge.20" "edge.21" lowertopology
edge create straight "vertex.14" "vertex.17"
edge cmove "edge.21" multiple 1 dangle 30 vector 0 0 1 origin 0 0 0
face split "face.9" edges "edge.21"
face split "face.9" edges "edge.22"
window modify shade
face delete "face.9" lowertopology
vertex delete "vertex.16"
volume create translate "face.10" vector 0 0 -0.1865
window modify shade
volume move "volume.2" offset 0 0 1.5
edge summarize "edge.17"
volume move "volume.2" offset 0 0 -0.1165
volume move "volume.2" dangle 5 vector 0 0 1 origin 0 0 0
volume move "volume.1" "volume.2" dangle -20 vector 0 0 1 origin 0 0 0
volume move "volume.1" "volume.2" dangle 90 vector 0 0 1 origin 0 0 0
save name "bismillah fan 1.dbs"
import iceminput "D:\\FLUENT LATIHAN\\Belajar Thesis\\fanstage\\naca1412.txt" \
edge
edge cscale "edge.35" multiple 1 factor 0.1 origin 0 0 0
edge cscale "edge.36" multiple 1 factor 0.1 origin 0 0 0
undo
/Undone to: edge cscale "edge.36" multiple 1 factor 0.1 origin 0 0 0
undo
/Undone to: edge cscale "edge.35" multiple 1 factor 0.1 origin 0 0 0
edge cscale "edge.35" multiple 1 factor 0.05 origin 0 0 0
edge cmove "edge.36" multiple 1 dangle 90 vector 0 1 0 origin 0 0 0
edge cmove "edge.37" multiple 1 dangle 90 vector 0 0 1 origin 0 0 0
edge delete "edge.38" lowertopology
edge delete "edge.35" lowertopology
edge delete "edge.36" lowertopology
edge create straight "vertex.65" "vertex.66"
/ERROR occurred in the next command!
face create wireframe "edge.37" real
face create wireframe "edge.37" "edge.38" real
face cmove "face.16" multiple 1 offset 0 0 1.5
window modify shade
face cmove "face.17" multiple 1 dangle 90 vector 1 0 0 origin 0 0 0
window modify shade
face delete "face.18" lowertopology
coordinate activate "c_sys.1"
/ERROR occurred in the next command!
volume create translate "face.17" vector 0 0 -0.1865
/ERROR occurred in the next command!
volume create translate "face.17" vector 0 0 -0.1865
/ERROR occurred in the next command!
volume create translate "face.17" vector 0 0 1
volume create translate "face.17" vector 1 0 0
window modify shade
volume cmove "volume.3" multiple 1 dangle 90 vector 0 0 1 origin 0 0 0
window modify shade
volume delete "volume.3" lowertopology
face create width 0.5 xyplane rectangle
face move "face.25" offset 0 0 -0.0705
volume split "volume.1" faces "face.25" connected
window modify shade
window modify noshade
edge create straight "vertex.73" "vertex.74" "vertex.13"
vertex create onedge "edge.64" percentarclength 0.7
vertex cmove "vertex.83" multiple 1 offset 0 0.1 0
vertex cmove "vertex.83" multiple 1 offset 0.1 0 0
coordinate create cartesian vertices "vertex.83" "vertex.85" "vertex.84"
/ERROR occurred in the next command!
face move "face.22" dangle 90 vector 0 1 0 origin 0 0 0
/ERROR occurred in the next command!
face move "face.22" dangle 90 vector 0 1 0 origin 0 0 0
face cmove "face.22" multiple 1 dangle 90 vector 0 1 0 origin 0 0 0
undo
/Undone to: face cmove "face.22" multiple 1 dangle 90 vector 0 1 0 origin 0 0 0
volume cmove "volume.4" multiple 1 dangle 90 vector 0 1 0 origin 0 0 0
volume delete "volume.4" lowertopology
volume cmove "volume.6" multiple 1 dangle -5 vector 0 1 0 origin 0 0 0
volume cmove "volume.7" multiple 1 dangle -5 vector 0 1 0 origin 0 0 0
volume delete "volume.6" "volume.7" lowertopology
edge summarize "edge.64"
volume cmove "volume.8" multiple 1 offset 0 0 -0.05
volume cmove "volume.9" multiple 1 offset 0 0 -0.05
undo
/Undone to: volume cmove "volume.9" multiple 1 offset 0 0 -0.05
volume cmove "volume.9" multiple 1 offset 0 0 -0.005
volume cmove "volume.10" multiple 1 offset 0 0 -0.005
volume cmove "volume.11" multiple 1 offset 0 0 -0.005
volume cmove "volume.12" multiple 1 offset 0 0 -0.005
volume delete "volume.10" "volume.9" "volume.11" "volume.12" lowertopology
volume subtract "volume.1" volumes "volume.13"
undo
/Undone to: volume subtract "volume.1" volumes "volume.13"
volume delete "volume.13" lowertopology
volume cmove "volume.8" multiple 1 dangle -5 vector 0 0 1 origin 0 0 0
undo
/Undone to: volume cmove "volume.8" multiple 1 dangle -5 vector 0 0 1 origin 0 0
volume cmove "volume.8" multiple 1 dangle 5 vector 0 0 1 origin 0 0 0
undo
/Undone to: volume cmove "volume.8" multiple 1 dangle 5 vector 0 0 1 origin 0 0 0
volume cmove "volume.8" multiple 1 dangle -5 vector 0 0 1 origin 0 0 0
volume cmove "volume.9" multiple 1 offset 0 0 -0.005
undo
/Undone to: volume cmove "volume.9" multiple 1 offset 0 0 -0.005
volume cmove "volume.9" multiple 1 offset 0 0 -0.05
volume cmove "volume.10" multiple 1 offset 0 0 -0.005
volume cmove "volume.11" multiple 1 offset 0 0 -0.005
volume cmove "volume.12" multiple 1 offset 0 0 -0.005
volume delete "volume.10" "volume.11" "volume.12" lowertopology
volume subtract "volume.1" volumes "volume.13"
undo
/Undone to: volume subtract "volume.1" volumes "volume.13"
undo
/Undone to: volume delete "volume.10" "volume.11" "volume.12" lowertopology
volume cmove "volume.13" multiple 1 offset 0 0 -0.005
volume cmove "volume.14" multiple 1 offset 0 0 -0.005
volume delete "volume.10" "volume.11" "volume.12" "volume.13" "volume.14" \
lowertopology
volume subtract "volume.1" volumes "volume.15"
window modify shade
volume cmove "volume.9" multiple 1 dangle 90 vector 0 1 0 origin 0 0 0
volume cmove "volume.10" multiple 1 dangle 90 vector 0 1 0 origin 0 0 0
volume cmove "volume.11" multiple 1 dangle 90 vector 0 1 0 origin 0 0 0
window modify shade
volume delete "volume.8" "volume.10" "volume.9" lowertopology
volume cmove "volume.12" multiple 1 offset 0 0 -0.1
volume cmove "volume.13" multiple 1 offset 0 0 -0.1
volume delete "volume.13" lowertopology
volume subtract "volume.2" volumes "volume.14"
volume delete "volume.11" "volume.12" lowertopology
volume delete "volume.5" "volume.1"
window modify noshade
face delete "face.27" "face.5" lowertopology
face delete "face.28" "face.8" lowertopology
face delete "face.25" lowertopology
window modify shade
face create wireframe "edge.4" "edge.15" "edge.58" "edge.10" "edge.56" \
"edge.14" real
window modify shade
window modify noshade
face create wireframe "edge.16" "edge.55" "edge.13" "edge.57" "edge.17" \
"edge.9" real
volume create stitch "face.3" "face.6" "face.29" "face.7" "face.26" "face.70" \
"face.92" "face.93" "face.4" real
vertex delete "vertex.15" "vertex.17" "vertex.19" "vertex.22" "vertex.23" \
"vertex.2" "vertex.3" "vertex.7" "vertex.8" "vertex.13" "vertex.73" \
"vertex.74" "vertex.83" "vertex.84" "vertex.85" "vertex.80" "vertex.82"
undo begingroup
edge picklink "edge.5"
edge mesh "edge.5" successive ratio1 1 intervals 15
undo endgroup
undo begingroup
edge picklink "edge.7"
edge mesh "edge.7" successive ratio1 1 intervals 30
undo endgroup
undo begingroup
edge picklink "edge.9"
edge mesh "edge.9" successive ratio1 1 intervals 5
undo endgroup
undo begingroup
edge delete "edge.9" "edge.4" keepsettings onlymesh
edge mesh "edge.9" "edge.4" successive ratio1 1 intervals 5
undo endgroup
undo begingroup
edge delete "edge.5" "edge.14" "edge.16" keepsettings onlymesh
edge mesh "edge.5" "edge.14" "edge.16" successive ratio1 1 intervals 15
undo endgroup
undo begingroup
edge delete "edge.16" "edge.17" "edge.15" keepsettings onlymesh
edge picklink "edge.15" "edge.17" "edge.16"
edge mesh "edge.16" "edge.17" "edge.15" successive ratio1 1 intervals 15
undo endgroup
undo begingroup
edge delete "edge.56" keepsettings onlymesh
edge picklink "edge.56"
edge mesh "edge.56" successive ratio1 1 intervals 10
undo endgroup
undo begingroup
edge delete "edge.56" "edge.55" "edge.57" "edge.58" keepsettings onlymesh
edge mesh "edge.56" "edge.55" "edge.57" "edge.58" successive ratio1 1 \
intervals 10
undo endgroup
undo begingroup
edge delete "edge.5" "edge.59" keepsettings onlymesh
edge mesh "edge.5" "edge.59" successive ratio1 1 intervals 15
undo endgroup
undo begingroup
edge delete "edge.7" "edge.62" keepsettings onlymesh
edge mesh "edge.7" "edge.62" successive ratio1 1 intervals 30
undo endgroup
undo begingroup
edge picklink "edge.128" "edge.125"
edge mesh "edge.125" "edge.128" successive ratio1 1 intervals 5
undo endgroup
undo begingroup
edge delete "edge.128" "edge.125" keepsettings onlymesh
edge mesh "edge.128" "edge.125" successive ratio1 1 intervals 10
undo endgroup
undo begingroup
edge delete "edge.130" "edge.129" keepsettings onlymesh
edge picklink "edge.129" "edge.130"
edge mesh "edge.130" "edge.129" successive ratio1 1 intervals 30
undo endgroup
undo begingroup
edge delete "edge.9" "edge.13" "edge.10" keepsettings onlymesh
edge mesh "edge.9" "edge.13" "edge.10" successive ratio1 1 intervals 5
undo endgroup
undo begingroup
edge delete "edge.10" "edge.21" "edge.26" keepsettings onlymesh
edge picklink "edge.26" "edge.21" "edge.10"
edge mesh "edge.10" "edge.21" "edge.26" successive ratio1 1 intervals 5
undo endgroup
undo begingroup
edge delete "edge.5" "edge.11" keepsettings onlymesh
edge mesh "edge.5" "edge.11" successive ratio1 1 size 0.0047938377
undo endgroup
undo begingroup
edge delete "edge.62" "edge.12" keepsettings onlymesh
edge picklink "edge.12" "edge.62"
edge mesh "edge.62" "edge.12" successive ratio1 1 size 0.0032579479
undo endgroup
undo begingroup
edge delete "edge.22" keepsettings onlymesh
edge picklink "edge.22"
edge mesh "edge.22" successive ratio1 1 intervals 15
undo endgroup
undo begingroup
edge delete "edge.22" "edge.24" keepsettings onlymesh
edge mesh "edge.22" "edge.24" successive ratio1 1 intervals 15
undo endgroup
undo begingroup
edge delete "edge.31" "edge.33" keepsettings onlymesh
edge picklink "edge.33" "edge.31"
edge mesh "edge.31" "edge.33" successive ratio1 1 intervals 35
undo endgroup
undo begingroup
edge delete "edge.33" "edge.31" "edge.34" "edge.32" keepsettings onlymesh
edge mesh "edge.33" "edge.31" "edge.34" "edge.32" successive ratio1 1 \
intervals 35
undo endgroup
undo begingroup
edge delete "edge.26" "edge.21" "edge.10" "edge.30" "edge.27" keepsettings onlymesh
edge mesh "edge.26" "edge.21" "edge.10" "edge.30" "edge.27" successive ratio1 \
1 intervals 5
undo endgroup
undo begingroup
edge delete "edge.24" "edge.29" "edge.28" keepsettings onlymesh
edge picklink "edge.28" "edge.29" "edge.24"
edge mesh "edge.24" "edge.29" "edge.28" successive ratio1 1 intervals 15
undo endgroup
undo begingroup
edge delete "edge.129" "edge.130" "edge.166" "edge.165" keepsettings onlymesh
edge mesh "edge.129" "edge.130" "edge.166" "edge.165" successive ratio1 1 \
intervals 30
undo endgroup
undo begingroup
edge delete "edge.128" "edge.125" "edge.162" "edge.163" keepsettings onlymesh
edge mesh "edge.128" "edge.125" "edge.162" "edge.163" successive ratio1 1 \
intervals 10
undo endgroup
undo begingroup
edge delete "edge.125" "edge.128" keepsettings onlymesh
edge mesh "edge.125" "edge.128" successive ratio1 1 intervals 10
undo endgroup
face mesh "face.3" "face.6" "face.10" "face.12" "face.13" "face.14" "face.15" \
"face.29" "face.4" "face.7" "face.26" "face.66" "face.70" "face.87" \
"face.91" "face.92" "face.93" triangle size 1
/ERROR occurred in the next command!
volume mesh "volume.2" "volume.3" tetrahedral size 1
/ERROR occurred in the next command!
volume mesh "volume.2" "volume.3" tetrahedral size 1
undo begingroup
face delete "face.3" "face.6" "face.10" "face.12" "face.13" "face.14" \
"face.15" "face.29" "face.4" "face.7" "face.26" "face.66" "face.70" \
"face.87" "face.91" "face.92" "face.93" onlymesh
face mesh "face.3" "face.6" "face.10" "face.12" "face.13" "face.14" "face.15" \
"face.29" "face.4" "face.7" "face.26" "face.66" "face.70" "face.87" \
"face.91" "face.92" "face.93" triangle size 0.01
undo endgroup
/ERROR occurred in the next command!
volume mesh "volume.2" "volume.3" tetrahedral size 1
/ERROR occurred in the next command!
volume mesh "volume.2" tetrahedral
face delete "face.3" "face.6" "face.10" "face.11" "face.12" "face.13" \
"face.14" "face.15" "face.29" "face.4" "face.7" "face.26" "face.66" \
"face.70" "face.87" "face.91" "face.92" "face.93" onlymesh
undo begingroup
edge delete "edge.166" "edge.165" keepsettings onlymesh
edge picklink "edge.165" "edge.166"
edge mesh "edge.166" "edge.165" successive ratio1 1 intervals 100
undo endgroup
volume mesh "volume.2" tetrahedral
undo begingroup
edge delete "edge.129" "edge.130" keepsettings onlymesh
edge mesh "edge.129" "edge.130" successive ratio1 1 intervals 100
undo endgroup
volume mesh "volume.3" tetrahedral
save name "bismillah fan 2.dbs"
export fluent5 "bismillah fan 2.msh"
edge delete "edge.130" "edge.129" "edge.62" "edge.59" "edge.58" "edge.56" \
"edge.12" "edge.11" "edge.10" "edge.32" "edge.31" "edge.22" "edge.21" \
"edge.24" "edge.15" "edge.14" "edge.5" "edge.4" "edge.7" lowertopology onlymesh
undo
/Undone to: edge delete "edge.130" "edge.129" "edge.62" "edge.59" "edge.58" "edge
edge delete "edge.63" "edge.64" "edge.7" "edge.4" "edge.5" "edge.10" \
"edge.11" "edge.14" "edge.15" "edge.56" "edge.59" lowertopology
face delete "face.16" lowertopology
coordinate delete "c_sys.2" "c_sys.3"
window modify invisible mesh
physics create "SHADOW-23" btype "PERIODIC" face "face.15"
physics create "PERIODIC-22" btype "PERIODIC" face "face.12"
physics create "PRESSURE OUTLET STATOR" btype "PRESSURE_OUTLET" face \
"face.11"
physics create "PRESSURE INLET STATOR" btype "PRESSURE_INLET" face "face.10"
physics create "STATOR SHROUD" btype "WALL" face "face.14"
physics create "STATOR BLADE" btype "WALL" face "face.91" "face.87"
physics create "STATOR HUB" btype "WALL" face "face.13"
physics create "SHADOW 12" btype "PERIODIC" face "face.93"
physics create "PERIODIC 11" btype "PERIODIC" face "face.92"
save
physics create "PRESSURE INLET ROTOR" btype "PRESSURE_INLET" face "face.3"
physics create "PRESSURE OUTLET ROTOR" btype "PRESSURE_OUTLET" face "face.4"
physics create "ROTOR INLET HUB" btype "WALL" face "face.6"
physics create "ROTOR BLADE" btype "WALL" face "face.70" "face.66"
physics create "ROTOR SHROUD" btype "WALL" face "face.7"
physics create "ROTOR INLET SHROUD" btype "WALL" face "face.29"
physics create "ROTOR HUB" btype "WALL" face "face.26"
physics create "FLUID ROTOR" ctype "FLUID" volume "volume.3"
physics create "FLUID STATOR" ctype "FLUID" volume "volume.2"
save
/ERROR occurred in the next command!
export fluent5 "bismillah fan 2.msh"
physics modify "SHADOW-23" btype label "SHADOW-23A" face "face.15"
/ERROR occurred in the next command!
export fluent5 "bismillah fan 2.msh"
physics modify "SHADOW-23A" btype label "SHADOWSTA" face "face.15"
physics modify "PERIODIC-22" btype label "PERIODICSTA" face "face.12"
physics modify "SHADOW 12" btype label "SHADOWROT" face "face.93"
physics modify "PERIODIC 11" btype label "PERIODICROT" face "face.92"
save
&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& &&&

sheikh nasir January 30, 2012 08:20

sliding mesh
 
hi
i am using sliding mesh technique 2D analysis for train moving in tunnel. but not able to work properly , can any body help me
i had done following steps
1. made two separate models in gambit so that i can combine them in fluent
2. export them to fluent and fuse them their
3. checked grid , it was done
now i had to use boundary conditions ( mesh motion) and grind interface, but i am not able to that. plz can any one tell me am i doing perfectly and how to proceed further.
thanks :confused:

siyamak April 10, 2013 00:44

Coefficient matrix for Finite Volume method with periodic boundary in x direction
 
Hello,

Help please!

I wrote a 2D finite volume code for a rectangular using Neumann boundary in bottom, Dirichlet boundary at top and periodic boundary in x direction. I get some results and everything seems to be fine other than by results tilted toward right boundary and I'm assuming that is because of NOT applying correct periodic boundary condition. Could you please let me know how to build a coefficient matrix which have periodic boundary in x direction?

I appreciate if anybody can help me with that.

myaccount January 22, 2014 05:11

Concept of periodic conditions
 
Hi,
How can we use same periodic conditions to
1.flow with a pressure drop,which is geometrically periodic in nature,and is not fully developed
and also to
2.Flow with a pressure drop,and fully developed flow(like fully developed flow through circular pipe)
Iam getting confused.Any body please clarify.


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