CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > CFX

Re: Coal combustion in tangential furnace

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   November 3, 2007, 03:03
Default Re: Coal combustion in tangential furnace
  #1
DG
Guest
 
Posts: n/a
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
  Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Problem on EDC model for coal combustion lei FLUENT 4 September 3, 2015 10:39
Turbulent Dispersion for Coal Combustion gravis CFX 2 March 24, 2010 00:56
Coal combustion and ash reaction kinetics sega Fluent UDF and Scheme Programming 0 January 21, 2010 09:05
Coal combustion in tangential furnace Jarek CFX 9 November 12, 2007 10:50
moisture in coal combustion Sheng FLUENT 3 June 15, 2003 20:43


All times are GMT -4. The time now is 22:08.