CFD Online Discussion Forums - Explicit source term implementation

Hi all,

I am trying to implement a reaction heat source term into the temperature equation of a clone of buoyantBoussinesqPimpleFoam. The source term is given by

Code:

Q_T/(rho_compat*rhok*cp)

Q_T is computed explicitly based on chemical mole fractions.

I have plotted Q_T to verify that it is being properly computed. The maximum value of Q_T is on the order of 3.4e-2.

The T equation implementation looks like this:

Code:

fvScalarMatrix TEqn

    (

        fvm::ddt(T)

      + fvm::div(phi, T)

      - fvm::laplacian(alphaEff, T)

     ==

        radiation->ST(rhoCpRef, T)

        + fvOptions(T)

        + Q_T/(rho_compat*rhok*cp)

    );



    TEqn.relax();



    fvOptions.constrain(TEqn);



    TEqn.solve();

However, when I run the case with an initial, uniform temperature distribution of 300K, the temperature distribution does not change and no buoyancy effects can be seen.

The OpenFOAM programmer's guide suggests (in a footnote on page P-35) that this implementation should be sufficient for an explicit source term.

I have also made an attempt to use fvOptions, but I have struggled to find sufficient documentation.

Suggestions are welcome.

Thanks!