Hi! I am modelling solid fuel combustion in a furnace with pdf preprocessor. The composition of the fuel (defined in pdf) is: C, H, N, O and its lower calorific value is 22.5 MJ/kg. I imported pdf in fluent and I reached convergence. When I calculate the volume integral of DPM enthalpy source I obtain a number that is very different from heat released by fuel combustion defined as (fuel mass flow rate * lower calorific value). The question is: How does Fluent calculate the heat released by fuel combustion? What does "volume integral of DPM enthalpy source" represent? Please, help me... Thanks a lot!!!

Volume integral of DPM enthalpy source should be the heats of formation times mass of each of species released from condensed phase plus the DPM sensible enthalpy source if any. The volume integral of DPM enthalpy source should equal the net heat transfer obtained from the flux panel of enthalpy in the report menu, when the case is converged.

Not really sure how the pdf model factors into this.