CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Running, Solving & CFD

coupled source term in 3 transport equations

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

Reply
 
LinkBack Thread Tools Display Modes
Old   February 26, 2011, 05:14
Default coupled source term in 3 transport equations
  #1
New Member
 
Muhammad reza hassani
Join Date: Apr 2010
Posts: 29
Rep Power: 6
mhassani is on a distinguished road
Dear Foamers
I want to revise icoFoam to include three transport equations solving for C1, C2, and C3. the problem is that they are coupled in their source term. I have included "CEqn.H" in my transportFoam (revised icoFoam).
I have a constant depending on C3 (third species concentration) which is used in C1, and C2. There are also source term in C2, and C3 equations depending on C1. I faced some questions regarding this:

1st question: Is it correct to use "fvm:Sp(kpa,C1)" in transport equation of C2? or I can simply use "...+ kpa*C1" so it is accounted explicitly? (in the equations kpa and landJ are constants which are calculated and given in transportProperties, respectively)

2nd question: shall I have a loop to converge (solving equations sequentially)? If I do, I have to calculate the difference between each iteration results. Shall I declare a new variable to save each iteration results so I can have comparison in each iteration.

3rd Question:Is it correct to declare and initialize some constants (e.g. omega, kpa in the code below) in the "CEqn.H"? they are to be calculated after C3 equation is solved.


//CEqn.H
double kpa; // constant calculated after C3 is calculated
double omega; //constant calculated after C3 is calculated
double C3Crit=2; //a constant
solve(
fvm::ddt(C3)
+fvm::div(phi,C3)
-fvm::laplacian(Dm3,C3)
-fvm::Sp(landJ,C1)
);
omega= C3/C3Crit;
if(omega >=1)
kpa=omega;
else
kpa=0;

solve
(
fvm::ddt(C1)
+fvm::div(phi,C1)
-fvm::laplacian(Dm1,C1)
+fvm::SuSp(kpa,C1)
);
//.................
solve
(
fvm::ddt(C2)
+fvm::div(phi,C2)
-fvm::laplacian(Dm2,C2)
+fvm:Sp(kpa,C1)
)
//...........
I would appreciate your help. thanks in forward.
Best regards
mhassani is offline   Reply With Quote

Reply

Thread Tools
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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
wmake compiling new solver mksca OpenFOAM Programming & Development 13 August 18, 2014 23:26
additional subdomain source term YJZ CFX 1 July 13, 2010 20:02
Adding a momentum source term segersson OpenFOAM Running, Solving & CFD 5 March 3, 2006 00:06
Problem: buoyancy source term for KE-EP model Andrey V.Ivanov Phoenics 0 May 23, 2003 04:50
UDF's - linearizing a negative source term Steve Howell FLUENT 1 March 18, 2001 17:21


All times are GMT -4. The time now is 04:47.