CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

SOFC temp. dependant i_o

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   September 22, 2013, 08:40
Default SOFC temp. dependant i_o
  #1
New Member
 
Carlos
Join Date: Sep 2013
Posts: 2
Rep Power: 0
SOFC is on a distinguished road
Hi

I am currently working with the SOFC unresolved electrolyte addon-module. From what can be seen in the "Activation Parameters" window, the temperature dependant exchange current density is the same for the anode and cathode, as you can only define one constant A and one constant B. The equation is as follows:

i_o=A*exp(-1/(BT))

Theoretically, and due to the -very- different materials used for cathode and anode, four constants should be defined (2 A's and 2 B's). My two questions are:

1. When the temp. dep. I_o equation is being used, the values written in "Constant Exchange Current Densities" are useless, right?

2. Would it be easy to define two constants A and two constants B modifying the consit.c file? If yes, usually the parameter A is not a constant but temperature dependent too (A= Constant*T). Would it be possible to make it temp. dependent?


Thanks beforehand!
SOFC is offline   Reply With Quote

Old   March 25, 2014, 04:52
Default
  #2
New Member
 
Christoph Schluckner
Join Date: May 2013
Posts: 4
Rep Power: 12
Schluckner is on a distinguished road
Hello,

I am facing a very similar problem! I am using the SOFC with unresolved electrolyte Module.

I was wondering if you still use the temperature dependant correlation for i_0 ?
In order to fit my simulation results to experimental data it would be necessary to make the anode exchange current density temperature dependant.
Unfortunately the calculated values for coeff. A and B won´t deliver the results as expected.
The c-file (constit.c) states, that if the temperature dependant i_0 is enabled, the above mentioned exponential correlation should be used.
Various simulations showed, that the values set for constant anode and cathode exch. curr. density still influence the calculated cell voltage.

So, my question is, if you were able to figure out a solution for your problem ? In the c-file it seems to me, that the temp. dependant i_0 is linked to the cathodic reaction, because the if-query combines the int-variable "temperature dependant i_0" and an equation called "Eq_O2", which indicates the cathodic reaction.

Best regards,

C.
Schluckner is offline   Reply With Quote

Old   January 6, 2015, 00:27
Smile facing problem in specifying activation energy
  #3
New Member
 
manikanta
Join Date: Jan 2015
Location: bangalore
Posts: 4
Rep Power: 11
manikanta is on a distinguished road
hi guys i am beginner in ansys fluent, i am facing problem in specifying activation energy, there is no particular information available on activation energy in ansys fluent tutorial of fuel cell, please guys if possible send me the procedure from beginning
my mail id is manikantadevarmani@gmail.com
if possible send video of the procedure

thanks a lot advance
manikanta 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
SOFC with Fluent's Fuel Cell Model D Bhardwaj ANSYS 6 March 30, 2018 11:59
sofc geometry drawing with gambit. shunjie FLUENT 1 January 28, 2018 13:32
CFB+wall BC for solid vel and gran temp Umesh FLUENT 2 September 10, 2013 17:21
udf-time dependant temp boundary prithiv Siemens 2 January 29, 2009 00:14
REAL GAS UDF brian FLUENT 6 September 11, 2006 08:23


All times are GMT -4. The time now is 02:50.