[Simranjeet Kaur]

Hi,

Has anyone had experience with modelling a co-fired combustion between biomass and coal?

How do i model the coal and biomass streams via species transport model if I only have the proximate and ultimate analysis of the individual fuels?

Thanks.

[alainislas]

I know it's a bit late, but I leave some suggestions for further users interested on the topic:

In Fluent, you can model coal & biomass combustion via DPM + Species Transport Model + EDM/finite-rate chemistry.

(1) Define separate DPM injections for coal and biomass. You can use the coal-calculator to estimate the pseudo-volatile molecule given the UA & PA of both fuels. Note that you'll have to repeat the calculation twice. By default, the coal-calculator output is a template of a mixture named -coal,volatiles-air-. In case of co-firing with biomass, you will have to add other species as required.

(2) Combustion of both fuels are quite similar: (1) moisture evaporation, (2) devolatilization, and (3) surface reactions. You can enable the first reaction for both fuels by enabling "wet combustion" and defining an appropiate liquid fraction (%vol). The devolatilization is significantly different. For coal you can use CPD, but for biomass it's better to determine your devolatilization kinetics and use a SFOM or Kobayashi model. Surface reactions can involve char oxidation, or some gasification reactions, it depends.