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-   -   Species Transport model (http://www.cfd-online.com/Forums/fluent/33557-species-transport-model.html)

Karthick April 22, 2004 09:54

Species Transport model
 
Hello All

Now I am dealing with Species Transport Model. I am having some doubts. I am having around 8 fluidisation reactions. But corresponding rate exponents, Activation energy, Preexponential factor, mixing law and other parameters, I don't know. All are mostly experiment related aspects. Is there are any sources where I can get all these values?

Also what is the possibility in Species transport model to specify whether the reaction is exothermic or endothermic?

Regards Karthick

co2 April 22, 2004 10:22

Re: Species Transport model
 
wiht exho or endo i guess you can just do that by changing the sign of energy source term in your zone

Karthick April 22, 2004 11:01

Re: Species Transport model
 
Dear co2

How I can specify exothermic and endothermic for each reaction. Totally I am having 8 reactions that has to take place in all the zones. It is just gasification reactions.

Also where I can get the activation energy, preexponential factor, rate exponent values?

Regards Karthick

co2 April 22, 2004 11:21

Re: Species Transport model
 
NIST has a very good web resource.

http://www.nist.gov/srd/onlinelist.htm

you got to be able to pick up something

Allan Walsh April 22, 2004 11:49

Re: Species Transport model
 
Not sure what type of project you are working on, but it sounds like you are just starting out. If you are doing this as a student project, then you can find many sources of kinetic rate data on the Internet with a quick search, which should suffice.

If this is a "real world" project, you probably should know that people spend years or decades trying to get the information needed. More rigorous reaction schemes may involve hundreds of species. Sure, this can be reduced to a simple rate expression, but is it valid for your conditions? Good enough? Takes lots of time to check these things.

Exothermic versus endo depends on what is entered for the heats of formation of reactants and products. Fluent 6.x has lots of stuff built into the database.

A good place to start is by first looking at the documentation, and then asking questions.


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