How to calculate heatflux using scalarSemiImplicitSource with absolute mode?
 

Dear foamer:
I have define a 0.05*0.05*0.05 box and use fvOptions to define heatflux to it.
The problem becomes what should be the value in xxx so the heat flux for the volume can be 20w?
I think q=c*m*dt, but is it correct? what is c, cv or cp? what is dt?
This is my code:
heatSource
{
type scalarSemiImplicitSource;
active true;

scalarSemiImplicitSourceCoeffs
{
selectionMode cellSet; // all, cellSet, cellZone, points
cellSet heatSource;
volumeMode absolute; // absolute;
injectionRateSuSp
{
T (xxx 0);
}
}
}