CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Programming & Development

Incompatible field operations

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 18, 2013, 04:27
Default Incompatible field operations
  #1
Member
 
Rohith
Join Date: Oct 2012
Location: Bayreuth, Germany
Posts: 45
Rep Power: 4
RaghavendraRohith is on a distinguished road
Hi

I am Actually trying to solve enthalpy equation using a logic but i am in need to add a source term to it.

But it delivers a message called Incompatible field operations, however i know that it is trying to solve two variables in one equation which should be an error.

1. But i have even tried to solve it in a different set and including the variable value here

2. I have aldready tried an explicit approach but doesnt work.

Here is the Code

Code:
{
  fvScalarMatrix hbEqn
        (
            fvm::div(phib, hb)
              - fvm::Sp(fvc::div(phib), hb)
              - fvm::laplacian(turbulenceb->alphaEff(), hb)
             ==
              - fvc::div(phib, 0.5*magSqr(Ub), "div(phib,K)")+ activBereichb*(alphab*Ts-fvm::Sp(alphab,Tb))      
        );

        hbEqn.relax();
        hbEqn.solve();

    pZonesb.addEnthalpySource(thermob, rhob, hbEqn);

    hbEqn.relax();

    hbEqn.solve();

    thermob.correct();


}
Ts is the temperature of solid and Tb is of fluid. There is a heat transfer between them which is to be included as an additional source term.


Thank you in Advance
RaghavendraRohith is offline   Reply With Quote

Old   July 19, 2013, 08:49
Default
  #2
New Member
 
Klas J
Join Date: Oct 2011
Location: Göteborg, Sweden
Posts: 10
Rep Power: 5
KlasJ is on a distinguished road
Hi,

Without having tested your code I guess the problem comes from the part:

Code:
activBereichb*(alphab*Ts-fvm::Sp(alphab,Tb))
In general fvm is used for the implicit discretization and fvc for the explicit discretization. Just as you say, and as is stated by the error message, you are not allowed to solve for more than one variable in each equation. In the first part of your equation your using hb as your implicit variable and in the right hand side you are trying to use implicit discretization also for Tb.

I guess you want to use the explicit name space (fvc) for all the factors in the right hand side.

I hope this was giving some clarity.

Best regards,

Klas
KlasJ is offline   Reply With Quote

Old   July 19, 2013, 08:52
Default
  #3
Member
 
Rohith
Join Date: Oct 2012
Location: Bayreuth, Germany
Posts: 45
Rep Power: 4
RaghavendraRohith is on a distinguished road
Hi Klas

I have solved the problem with this aspect . Actually it was due to the same reason.

I tried to figure it out.

Thanks a lot

Rohith
RaghavendraRohith 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
Moving mesh Niklas Wikstrom (Wikstrom) OpenFOAM Running, Solving & CFD 122 June 15, 2014 06:20
Incompatible Field of operation tayo OpenFOAM 2 December 11, 2012 16:04
Is good initial guess field is neccessary ? mmkr825 OpenFOAM 5 October 17, 2012 12:58
problems after decomposing for running alessio.nz OpenFOAM 5 April 20, 2011 08:44
Problem with rhoSimpleFoam matteo_gautero OpenFOAM Running, Solving & CFD 0 February 28, 2008 07:51


All times are GMT -4. The time now is 22:47.