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

PEM Fuel cell module meshes. ICEM vs workbench

Register Blogs Members List Search Today's Posts Mark Forums Read

Like Tree6Likes

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   February 24, 2011, 12:36
Default PEM Fuel cell module meshes. ICEM vs workbench
  #1
New Member
 
Adam Arvay
Join Date: Feb 2011
Posts: 23
Rep Power: 15
aarvay is on a distinguished road
I'm trying to create a mesh for a PEM fuel cell using ICEMCFD and I'm having a heck of a time getting it to converge. I feel like there is something obvious I am missing and so I'm appealing to the community to help me find my mistake. This is all in version 12.1

I've gone back to the demo fuel cell which is described in this tutorial(Modeling a Single-Channel, counter-flow polymer electrolyte membrane (PEM) Fuel cell). I got it from the fluent site somewhere, but I can't find where I originally found it. This document talks about meshing using gambit or something, but I was able to mostly replicate the results by using workbench meshing. I've found the workbench mesher to be inadequate for more complicated geometries so I've switched to using ICEM CFD.

now I am trying to do the tutorial using ICEM to mesh the geometry and its not working. I'm able to generate a mesh (using cartesian grid method) and it seems like a good mesh to me, but it will not converge in Fluent. I have attached case files for each type, workbench mesh and the ICEM mesh. You will need to have the fuel cell license available to actually intialize the solution. The Workbench mesh does converge (well atlesat it doesn't immediately diverge) while the ICEM mesh immediately explodes.

I'm trying to understand the differences between these two meshes and why one works and one doesn't. I'm asking anyone that knows anything about the FC module to load up these two cases and tell me why the Workbench one works and the ICEM one doesn't. And also some suggestions on how to fix it.


Workbench case file
ICEM case file

I can provide related geometry/mesh files if you think that will help you.

Thanks for any info.

For future reference you can find the fuel cell module manual here

Last edited by aarvay; February 24, 2011 at 15:17. Reason: added version 12.1
aarvay is offline   Reply With Quote

Old   February 24, 2011, 22:54
Default
  #2
New Member
 
Adam Arvay
Join Date: Feb 2011
Posts: 23
Rep Power: 15
aarvay is on a distinguished road
the one thing I can notice that seems to be important is the creation of shadow walls. In the workbench mesh, shadow walls are only created at the boundary between solid and fluid parts. In the ICEM mesh, shadow walls are being created at boundary of every part. I suspect this is the cause of my issues but I do not know how to resolve it.
aarvay is offline   Reply With Quote

Old   February 25, 2011, 00:57
Default
  #3
New Member
 
Adam Arvay
Join Date: Feb 2011
Posts: 23
Rep Power: 15
aarvay is on a distinguished road
Well I figured out my problem. It turns out it was something trivially simple. The two meshes had different physical sizes. I suppose the ICEM meshes default to meter scale, while the other was in mm. So the non-working mesh was 1000x larger than the other. Hopefully someone else will find this helpful.

edit for my own future reference: There was in fact a problem with those shadow walls. I was able to work around it by setting my material properties accordingly (solids and liquids) then turning one of the wall/shadow-wall pairs into an internal. I did this to all shadow walls in the geometry. I could not change shadow walls at liquid-solid interfaces into internals which is exactly how it should be.

Last edited by aarvay; February 25, 2011 at 14:51. Reason: for my own information
aarvay is offline   Reply With Quote

Old   October 28, 2011, 00:00
Smile ask for advise
  #4
LWX
New Member
 
LiuWenxiu
Join Date: Oct 2011
Posts: 3
Rep Power: 15
LWX is on a distinguished road
I think I have encountered the same difficulties as you have by modeling the same case(Tutorial: Modeling a Single-Channel, Counter-Flow Polymer
Electrolyte Membrane (PEM) Fuel Cell),While I use the Gambit to get the mesh file.There is still something wrong with the mesh after several modifications and now I can't find where the problem is as I think my mesh is perfect.Utill last night,I read your post and I think you can help me.The words below illustrate the warnning when I import the mesh file into the FLUENT.
Warning: Thread 18 has 2 contiguous regions.
Warning: Thread 19 has 2 contiguous regions.
creating wall-gdl-c-shadow
creating wall-gdl-a-shadow
creating wall-ch-c-shadow
creating wall-ch-a-shadow
shell conduction zones,
Done.

I am a Chinese and my English is poor,so expect you can understand the words above.What's more,this is my first time to loggin this forum.
LWX is offline   Reply With Quote

Old   October 28, 2011, 22:47
Default
  #5
New Member
 
Adam Arvay
Join Date: Feb 2011
Posts: 23
Rep Power: 15
aarvay is on a distinguished road
Quote:
Originally Posted by LWX View Post
I think I have encountered the same difficulties as you have by modeling the same case(Tutorial: Modeling a Single-Channel, Counter-Flow Polymer
Electrolyte Membrane (PEM) Fuel Cell),While I use the Gambit to get the mesh file.There is still something wrong with the mesh after several modifications and now I can't find where the problem is as I think my mesh is perfect.Utill last night,I read your post and I think you can help me.The words below illustrate the warnning when I import the mesh file into the FLUENT.
Warning: Thread 18 has 2 contiguous regions.
Warning: Thread 19 has 2 contiguous regions.
creating wall-gdl-c-shadow
creating wall-gdl-a-shadow
creating wall-ch-c-shadow
creating wall-ch-a-shadow
shell conduction zones,
Done.

I am a Chinese and my English is poor,so expect you can understand the words above.What's more,this is my first time to loggin this forum.
Hey,

Fluent will automatically create shadow walls at interfaces between solid and liquid zones in your mesh. This is normal and you should be able to run your simulation without any issues.


If you are having problems, I don't think the shadow walls are the cause. What are problems are you having?
aarvay is offline   Reply With Quote

Old   October 30, 2011, 03:41
Default
  #6
LWX
New Member
 
LiuWenxiu
Join Date: Oct 2011
Posts: 3
Rep Power: 15
LWX is on a distinguished road
I specified all the interfaces as "interface" in the boundary condition panel while meshing in the Gambit first time and the Fluent gived me the warnings above and checked the mesh failed with the warnings like:Unassigned interface zone detected for interface 11. Then I modified all the interfaces boundary conditions to interior boundary condition and the warnning still appeared while there was nothing wrong when checking the mesh. So I want to know how you specified the boundary conditions especially the face between the flow channel and the GDL.

Last edited by LWX; October 30, 2011 at 05:37.
LWX is offline   Reply With Quote

Old   October 31, 2011, 12:15
Default
  #7
New Member
 
Adam Arvay
Join Date: Feb 2011
Posts: 23
Rep Power: 15
aarvay is on a distinguished road
Quote:
Originally Posted by LWX View Post
I specified all the interfaces as "interface" in the boundary condition panel while meshing in the Gambit first time and the Fluent gived me the warnings above and checked the mesh failed with the warnings like:Unassigned interface zone detected for interface 11. Then I modified all the interfaces boundary conditions to interior boundary condition and the warnning still appeared while there was nothing wrong when checking the mesh. So I want to know how you specified the boundary conditions especially the face between the flow channel and the GDL.
As you know, I generated my mesh using ICEM CFD and I didn't bother to assign any boundaries during mesh generation. By default in ICEM all the interfaces were walls. After I imported it into fluent, all of the interfaces were converted to wall/shadow wall pairs automatically by fluent. I left the solid/liquid interfaces as walls and changed the rest of the interfaces to internals.
aarvay is offline   Reply With Quote

Old   May 5, 2012, 14:52
Default
  #8
New Member
 
Emad
Join Date: Feb 2012
Location: Egypt
Posts: 26
Rep Power: 14
elemad1987 is on a distinguished road
Send a message via Skype™ to elemad1987
Hi Adam,
I had find your master thesis and read it, it was very useful to me.
I'm Emad from Egypt study master degree in PEM fuel cell in Assiut University.
I want to ask you a lot about your thesis, can you send an email to me, to know your mail.
Or can you send me your final case to understand how you did your mesh.
I want to ask you about mesh using ANSYS.
Regards,
Emad
elemad1987@gmail.com
elemad1987 is offline   Reply With Quote

Old   June 23, 2013, 08:31
Default Fuel Cell using Ansys Fluent
  #9
New Member
 
Diab
Join Date: Dec 2012
Posts: 5
Rep Power: 13
Diab is on a distinguished road
Hi,

I am a starter in the field of modeling the fuel cell using ansys fluent. May anybody provide me some sources from which I can learn how to perform my simulation

Thank you in advance
Diab is offline   Reply With Quote

Old   June 24, 2013, 22:00
Default
  #10
New Member
 
Adam Arvay
Join Date: Feb 2011
Posts: 23
Rep Power: 15
aarvay is on a distinguished road
Hey Diab,

I did take a stab at writing an intro manual for doing PEMFC modeling using fluent based on the notes I took while I was going through the process. I had planned on making this a much cleaner document and making it available but apparently i couldn't be bothered to. I don't like to release low quality work, but it will have to suffice since I don't think anything else exists along these lines. I've passed this thing around to a few people in emails and stuff, but I don't think I ever posted it online. Hopefully it is helpful.

Ansys fluent PEMFC manual
ghost82 and sabrina sabi like this.
aarvay is offline   Reply With Quote

Old   June 25, 2013, 04:07
Default
  #11
Senior Member
 
A CFD free user's Avatar
 
A-A Azarafza
Join Date: Jan 2013
Posts: 226
Rep Power: 14
A CFD free user is on a distinguished road
@ Adam, here's an opptunity for me to thank you very much for the intro manual you gave me. Thank you again and it helped me so much.
good luck
Prince Abraham likes this.
__________________
Regard yours
A CFD free user is offline   Reply With Quote

Old   June 25, 2013, 07:06
Default
  #12
New Member
 
Diab
Join Date: Dec 2012
Posts: 5
Rep Power: 13
Diab is on a distinguished road
Dear aarvay,

Thank you very much for the introduction manual. It seems very beneficial. I am really thankful

Best Regards
Diab is offline   Reply With Quote

Old   September 8, 2014, 15:15
Default
  #13
New Member
 
leila
Join Date: Sep 2014
Posts: 3
Rep Power: 12
leily is on a distinguished road
Hi
I want to simulate single PEM fuel cell using fluent 6.3 for study concentration and temperature distribution in the flow channels of the bipolar plates and performance of the PEM fuel cell. But I don't know, what do I need data to simulate?
Do I write the new UDF for this study?
can anyone explain to me step by step process of the simulation?
leily is offline   Reply With Quote

Old   September 8, 2014, 15:19
Default simulation of PEM fuel cell
  #14
New Member
 
leila
Join Date: Sep 2014
Posts: 3
Rep Power: 12
leily is on a distinguished road
Hi
I want to simulate single PEM fuel cell using fluent 6.3 for study concentration and temperature distribution in the flow channels of the bipolar plates and performance of the PEM fuel cell. But I don't know, what do I need data to simulate?
Do I write the new UDF for this study?
can anyone explain to me step by step process of the simulation?
leily is offline   Reply With Quote

Old   September 13, 2014, 01:52
Default
  #15
Senior Member
 
A CFD free user's Avatar
 
A-A Azarafza
Join Date: Jan 2013
Posts: 226
Rep Power: 14
A CFD free user is on a distinguished road
Quote:
Originally Posted by leily View Post
Hi
I want to simulate single PEM fuel cell using fluent 6.3 for study concentration and temperature distribution in the flow channels of the bipolar plates and performance of the PEM fuel cell. But I don't know, what do I need data to simulate?
Do I write the new UDF for this study?
can anyone explain to me step by step process of the simulation?
If you want to model what you mentioned in above statement, I should say no, there is no need to employing UDF in that case. But, it surely depends on what you looking for. If you want to know a more correct answer, you have to offer more details about the problem.
Regarding to the second question, there is a PEMFC tutorial you can find easily On web. I recommend that you do it first to get some insight of performing a real simulation in PEMFC system. doing the tutorial, you can understand at least what type of question you face in a typical PEMFC system and how to run a simple case.
Hoe it helps
__________________
Regard yours
A CFD free user is offline   Reply With Quote

Old   September 14, 2014, 08:08
Default
  #16
New Member
 
leila
Join Date: Sep 2014
Posts: 3
Rep Power: 12
leily is on a distinguished road
Quote:
Originally Posted by A CFD free user View Post
If you want to model what you mentioned in above statement, I should say no, there is no need to employing UDF in that case. But, it surely depends on what you looking for. If you want to know a more correct answer, you have to offer more details about the problem.
Regarding to the second question, there is a PEMFC tutorial you can find easily On web. I recommend that you do it first to get some insight of performing a real simulation in PEMFC system. doing the tutorial, you can understand at least what type of question you face in a typical PEMFC system and how to run a simple case.
Hoe it helps

Dear A-A Azarafza
Thank you very mach.
I want to compare the concentration and temperature distribution in the two types of the serpentine flow channels. I draw geometry in the Gambit and I run it by fluent according to manual.
I think, I entered incorrect boundary conditions. this photos clearly show the boundary conditions that I have set.
I don't know, these boundary condition are true or not true????
I don't know, why I can't see any result of residual in the curve???
I don't know, which areas should be related to the voltage jump?
these are my problems for draw geometry and run of a single PEMFC.
could you give me your email address that I sent photos and help me for solve these problems?
Thanks you so much.
best regards
leily is offline   Reply With Quote

Old   September 15, 2014, 11:21
Default Can you send me the finished file which can run smoothly
  #17
New Member
 
Nguyen Vinh
Join Date: Sep 2014
Posts: 1
Rep Power: 0
vinhgsyb is on a distinguished road
My email vinhgsyb@yahoo.com
vinhgsyb is offline   Reply With Quote

Old   July 10, 2015, 08:31
Default how to get polarization curve in fluent PEMFC model
  #18
New Member
 
Rana Saumy
Join Date: Dec 2014
Location: Gujarat, India
Posts: 6
Rep Power: 11
SAM_R is on a distinguished road
I'm using PEMFC addon module of fluent and model of single pem fuel cell channel was made in Gambit 2.4 according to below open online tutorial file:
ssadeghi.ir_tutorial_modeling_pem_fuel_cells

only my cell having active area of 16 cm2 & hence channel length is 40 mm.

with same flow rate or by lowering flow rate solution is converging on 0.02254 A/cm2.

where may I have made mistake?

I have gone through both threads of Adam Arvay, I have also read appendix of TUI of obayopo's thesis for gambit and Adam's for fluent help.

Almost all my problem have solved but above mentioned problem
SAM_R is offline   Reply With Quote

Old   July 10, 2015, 08:34
Default
  #19
New Member
 
Rana Saumy
Join Date: Dec 2014
Location: Gujarat, India
Posts: 6
Rep Power: 11
SAM_R is on a distinguished road
@ Adam Arvay
please mail me PEMFC Manual
mail:ranasaumy@gmail.com
SAM_R is offline   Reply With Quote

Old   July 13, 2015, 10:51
Question Can anyone suggest me anything about this INTERFACE boundary
  #20
New Member
 
Rana Saumy
Join Date: Dec 2014
Location: Gujarat, India
Posts: 6
Rep Power: 11
SAM_R is on a distinguished road
FLUENT's PEM add-on module supports the use of non-conformal grid interfaces. In such cases, it is recommended that the INTERFACE boundary type be used halfway between the membrane continuum zone, and that the mesh on opposite sides of the interface have similar size, aspect ratio, and orientation. In such cases, the membrane will consist of two fluid zones.

I can't understand above line.

Please help.
SAM_R is offline   Reply With Quote

Reply

Tags
fuel cell, pemfc module

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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
PEM fuel cell long iteration times inoxrocks FLUENT 2 August 7, 2012 08:36
PEM Fuel Cell Mesh shamsnoor FLUENT 0 May 27, 2009 17:30
PEM Fuel Cell Modeling with OpenFOAM Berker OpenFOAM 1 May 3, 2009 20:16
workbench geometry in ICEM Ross CFX 6 November 2, 2006 07:51
Warning 097- AB Siemens 6 November 15, 2004 05:41


All times are GMT -4. The time now is 09:29.