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-   -   What Damkohler number (http://www.cfd-online.com/Forums/fluent/41492-what-damkohler-number.html)

rams June 23, 2006 11:21

What Damkohler number
 
Hello Friend,

what is Damkohler number and how can i find it ,....

is it very essential to determine it to decide which model to use for combustion simulation,...

How to decide which model to use, using this number

Regards ,..

Rams

inkant June 23, 2006 12:24

Re: What Damkohler number
 
This number is a number which gives u a comparison of tubulent time scales and chemical time scales .... when turbulent time time become ver small it ... it is the turbulence which starts interacting with chwmistry .... may be combustion ..... in Fluent u have extremely slow ...(computationally expensive model) EDC .... eddy dissipation concept which takes turbulence into account apart from LES and DES simulations which are extremely computationally expensive. u can use this ...

Rams June 24, 2006 04:29

Re: What Damkohler number
 
I have solved a combustion problem using mixture fraction Pdf model without checking for damkohler number,...

Am having a problem with the solution,.. am getting negative pressures at nozzle throats,... is this bcoz i may have selected wrong model,..

i have even tried to solve the same problem with species transport model but i failed even to start the solution with that model,.....

what should i do,.. to get correct result,...


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