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-   -   Eddy Dissipation Model (http://www.cfd-online.com/Forums/main/5376-eddy-dissipation-model.html)

Thomas November 6, 2002 14:28

Eddy Dissipation Model
 
I am using the eddy dissipation model and have a question about the constants A(4) and B(0.5). What effect will changing either of these constants have on the reaction?

Volker November 7, 2002 05:50

Re: Eddy Dissipation Model
 
Hi,

The eddy dissipation model calculates the reaction rate as: Rf = -rho*epsilon/k*A*min[mf, mo/so, B*mp/sp]

where mf - fuel concentration, mo - oxidant conc., mp - product conc., so = no*Mo/nf*Mf and sp = np*Mp/nf*Mf

Constant A goes directly into the reaction rate. Constant B is supposed to have an influence on the temperature dependeny of the reaction (mp is linked to the temperature). Lowering B will make the reaction rate more dependent on the product concentration, while increasing it will make the reaction dependent on the fuel and oxidant concentrations.

You will probably have to play around with those two to get anything meaningful out of your calculations. Good luck!

Regards,

Volker

Thomas November 7, 2002 08:19

Re: Eddy Dissipation Model
 
Thanks for clearing that up. I understand what's going on now. :)


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