CFD Online Logo CFD Online URL
Home > Forums > FLUENT

Wood combustion initialization--help needed

Register Blogs Members List Search Today's Posts Mark Forums Read

Like Tree1Likes
  • 1 Post By roderick.blevins

LinkBack Thread Tools Display Modes
Old   May 28, 2013, 10:13
Default Wood combustion initialization--help needed
New Member
Join Date: May 2013
Posts: 1
Rep Power: 0
roderick.blevins is on a distinguished road
I am almost completely new to Fluent, but my Master's thesis is centered around constructing a CFD model for biomass (wood) combustion in a small cookstove. I am attempting to model said combustion using Species Transport while injecting "Combusting" Discrete Phase wood particles. However, I cannot seem to figure out how to achieve ignition without creating unrealistic boundary conditions for the application. Once combustion is begun I believe that my model can sustain it to steady-state; however, without setting a very high thermal wall boundary condition (which I would rather not do, as wall temperature is an output of interest) or constructing some high-temperature or heat-generating smaller volume (which I would rather not do, as it affects the outlet pollutant mass fractions and the feed rate of the fuel), I cannot seem to achieve combustion. Is there a way to initialize combustion in Fluent when attempting a steady-state simulation of this sort?

A relatively comprehensive bulleted list of my set-up:
  • Wood particles injected at ambient temperature through one inlet with a very low accompanying fluid flow velocity with a very small mass fraction of wood volatiles
  • A separate air inlet, also arriving at ambient temperature (300 K), with no mass fraction of volatiles
  • A "Mixed" thermal boundary condition incorporating external radiation and free convection on the exterior surface (or at least that's what I hope the convection is referring to) with a specified wall thickness
  • A pressure outlet boundary condition at the top of the geometry with a relatively high (1000 K plus) backwash temperature
  • Intuitively-set DPM boundary conditions for each (i.e. escape for all inlets/exits, reflect for wall--although if someone could explain the reflect settings I would appreciate it)

I believe that's it...I would sincerely appreciate any guidance or assistance that anyone could offer. As I'm said, I'm a complete rookie at Fluent and CFD in general, so I'm aware of my glaring inexperience. Thanks in advance. likes this.
roderick.blevins is offline   Reply With Quote

Old   July 25, 2013, 09:07
New Member
Join Date: Aug 2012
Location: stockholm
Posts: 4
Rep Power: 7 is on a distinguished road
Send a message via Yahoo to
Sorry, I don't have the answer to your question, I have a question of your kind almost;I am simulating a soaking pit furnace, used for reheating slabs in steel production route. I am not sure if I can use this "mixed thermal boundary condition" while working with furnaces, loaded with ingots (B.C of ingots' surface)... may I ask if you are using 'mixed' thermal boundary condition for the exterior walls, from inside? like you are considering it as the effect of heat transfer of combustion on the surface of walls? how sure you are of picking such a BC? I've been told that I can not use it since its inside the domain,.. is offline   Reply With Quote

Old   October 28, 2013, 17:14
Default Hi Roderik
New Member
Join Date: Apr 2013
Posts: 8
Rep Power: 6
bahramnourani is on a distinguished road
I think that u can use patch option after your initializing.I think that patch option let u to increase your temp for a moment.
bahramnourani is offline   Reply With Quote


combustion, ignition, wood

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Wood Devolatilation and Volatile combustion nutow FLUENT 1 February 18, 2015 03:35
combustion of wood shavings Özer AYDIN FLUENT 0 September 16, 2008 05:40
Simple approach - solid wood combustion (newbie..) Dan Main CFD Forum 0 December 3, 2007 03:06
combustion of wood Özer AYDIN FLUENT 4 June 25, 2007 03:11
wood shaving combustion Özer AYDIN FLUENT 0 November 23, 2006 07:52

All times are GMT -4. The time now is 00:04.