Hai

Can any one please help me, I am doing combustion study of a single droplet fuel in a oxidizer medium. I have choosen a rectangular chamber in which a spherical drop is placed at the centre for its droplet study. Oxidizer is injected through the top face.

For this study, I have used species transport and eddy dessipation modeling. But the after iteration it is observed that combustion is not taken place..Can any one please give any idea to proceed further..

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Where are the combustible species coming from? DPM model with volatiles release/char burning?

First of all thanks for your response.Species are the fuel droplet(ANILINE) at centre , which is stationary and oxygen gas are entering from the top face. In fluent how to specify all this model, I am not able to understand...Can you please help in specifying it...I have given boundary for fuel drop as velocity inlet. Bottom face as pressure outlet.All four side face as hot wall.Actually I am not getting how to specify all other model...In model I selected solver as segeregated,unsteady; energy equation; viscous with K-e model and species transport with volumetric and eddy dessipation...Please specify other parameter I should consider for the droplet to combust..

Do you get the correct amount of aniline released? You would probably be better to use a mass flow outlet boundary (and inlet).

What is the fuel supposed to do? Burn in an envelope around the droplet? Burn more globaly? What mechanism do you have for it to react? Species transport with corresponding reaction with oxygen? Do you have oxygen or air? If you have the reaction kinetically controlled, you may have to patch in an appropriate temperature to get the reaction started.

How is heat transferred from the hot walls? Convection only, or do you have radiation from the walls. Is the fluid entering the chamber hot enough? Do you have fine enough grid structure around the drop to resolve details of interest.

Once you get these things settled, it should be straight forward. Good luck.

Hi Thank you for your reply, I will follow all the instructions you said and if I am getting correct solution or not.Till now I have not considered accurately all that parameter...Once again thank you.