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-   -   Re: Coal combustion in tangential furnace (https://www.cfd-online.com/Forums/cfx/24776-re-coal-combustion-tangential-furnace.html)

DG November 3, 2007 02:03

Re: Coal combustion in tangential furnace
 
Hi Jarek, I am also facing the same problem while modeling 200MWe boiler. The temp shoots to 2400-3000K in furnace zone.

1. I am using Hex cells and Its sure that hex or tet does not matter temperature. This may lead to large numbers and computation time. Ur geometry is probably 11*14*53m. if ur in doubt then go for hex I am sure u will end up with less than 1.5 million cells.

2. I have performed few trial simulations with speci-transport with finite chemistry approach. The change in values of A or E in gas phase does not have much effect as these are very fast kinetics. first check the heat of formation specified for each species and confirm the heat generated. =1GW as in ur case.

3. Generally 5-10K particles tracking is sufficient for particle tracking. You can check this by just making double the current number of particles. You should get nearly same results.

4. What is ur energy,radiation,discrete phase urfs?

5. if ur using finite chemistry approach, then check

a) Which solver are u using? if ur fluent user then be careful while using directly the hv_vol/lv_vol etc. default species and their reactions. check stoichiometry of the reaction assumed.

b) quantity of volatile is same as calculated by ur solver

6. specify turbulence model check out this for ur case


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