Combusting Particles
 

Dear FLUENT users,

I am modeling solid particles combustion with FLUENT. Under materials panel, for the combusting particles, there are places for these 2 inputs: (1) Burnout Stochiometric ratio (2) Heat of reaction for burnout

In the user's guide, 'Burnout Stoichiometric ratio' is explained as mass of oxidant needed per mass of char; which will mean I will get the same 2.67 value for all types of coal or solids that undergone this reaction: char + O2 --> CO2, where char = C<s> material in FLUENT.

Similarly, for 'Heat of reaction for burnout', it is the heat released by surface char combustion reaction, i.e. the heat released per unit mass of char consumed in the reaction; so if I have this equation C<s> + O2 --> CO2 for different types of coal or solids, I will get the same value of 3.935e+08, i.e. the heat of reaction of C<s> + O2 -->CO2.

In short, no matter what solid I use, as long as the char reaction is C<s> + O2 --> CO2 , I will always get (1) as 2.67 and (2) as 3.935e+08. Does this really make sense? I suspect I'm wrong somewhere...can someone please help me?

Many thanks.

That is true..

And what about the % heat fraction absorbed by solid

Viscosity
 

Hello guys!!! i also have some problems with the non newtonian power law.
First of all i have to specify that I m a beginner in fluent.
I have a Pipe with non Newtonian fluid inside i do not have the lenght of my geometry but my fluid is fully developed (that means that the pipe should be pretty long to have this condition right?)
Well i draw my geometry and than i start to use fluent whe i define material and i put "water-liquid" than i select "viscosity-> Non newtonian power law" and then i should have minimun and maximum viscosity, but i don't, and i really don't know which kind of values i have to put and in which way i can ceck if they will be correct or not?Can you help me please? Thanks.:o