I need help for partially premixed combustion

motaz.medhat · November 24, 2019, 03:08

please can any one help me for understanding why this area around the flame is still cooled.

Untitled.jpg

Seps · November 25, 2019, 04:21

Hello!
Could you provide more info about the geometry?

motaz.medhat · November 25, 2019, 05:15

Quote:

Originally Posted by Seps

Hello!
Could you provide more info about the geometry?

Air inlet from two rectangular holes and fuel enter from 12 holes over the cylinder

Seps · November 25, 2019, 06:47

I still don't get the geometry, but anyway...
Combustion of a fuel jet needs a certain temperature and enough o2 to happen.
It's physically logical to find cold jets in flames, even if the temperature is high enough, the fuel has to reach a zone with o2 in order to react.
Maybe it helps you to think of the flame as layers: the external layers face the high temperature and o2 region and react, while the inner layers have to wait their turn to reach that region.
You can also read about turbulent and laminar flames, where you will find this phenomenon clearly.

November 24, 2019, 03:08	I need help for partially premixed combustion	#1
motaz.medhat New Member Moataz Join Date: Nov 2019 Posts: 7 Rep Power: 6	please can any one help me for understanding why this area around the flame is still cooled. Untitled.jpg

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
non premixed combustion with ''compressibility effects'' enabled	Muneeb	FLUENT	5	November 15, 2018 02:06
Modelling of premixed combustion in a burner rig	ThomasS	FLUENT	12	September 7, 2018 13:07
partial premixed combustion model early combustion than expected	omaradel	FLUENT	0	June 27, 2017 14:38
How to model premixed combustion using partially premixed combustion model in Fluent?	sab10012	FLUENT	0	October 6, 2015 01:18
Partially Premixed Combustion - Direct Fired Boiler	oknus	FLUENT	0	April 10, 2012 10:52

November 25, 2019, 04:21		#2
Seps New Member Join Date: Feb 2015 Posts: 10 Rep Power: 11	Hello! Could you provide more info about the geometry?

November 25, 2019, 06:47		#4
Seps New Member Join Date: Feb 2015 Posts: 10 Rep Power: 11	I still don't get the geometry, but anyway... Combustion of a fuel jet needs a certain temperature and enough o2 to happen. It's physically logical to find cold jets in flames, even if the temperature is high enough, the fuel has to reach a zone with o2 in order to react. Maybe it helps you to think of the flame as layers: the external layers face the high temperature and o2 region and react, while the inner layers have to wait their turn to reach that region. You can also read about turbulent and laminar flames, where you will find this phenomenon clearly.