CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > ANSYS > FLUENT > Fluent UDF and Scheme Programming

source terms problem-hybrid combustion

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

LinkBack Thread Tools Search this Thread Display Modes
Old   March 29, 2010, 07:50
Default source terms problem-hybrid combustion
New Member
qiang xia
Join Date: Mar 2009
Posts: 8
Rep Power: 11
alanlove is on a distinguished road
I am modeling the hybrid rocket motor combustion chamber, so there is an oxidizer flow perpendicular to the fuel flow. A diffusion flame exists over a solid fuel. The heat transfer between the diffusion flame and solid fuel should be considered.
I define a thin fluid zone adjacent to the fuel surface, then mass source term, radial momentum source term, species source term and energy source term can be defined relative to the specified mass flux. Consequently, pyrolysis species to enter the domain whilst being able to calculate heat transfer at the fuel surface by setting it as a wall BC.
My source terms are as followings:
mass source term: m/V=rhoS*A*r/V
radial momentum source: mv/V
species source term: m/V=rhoS*A*r/V (when the fuel pyrolysising, only one species was considered, in my opinion, the species source term is equal to mass source term )
energy source term: m*S_e/V
which V is the cell volume, rhoS is the solid fuel density, A is the cell area,v is the pyrolysising velocity, S_e is the formation enthalpy and r is the regression rate of solid fuel, and can be expressed as arrhenius equation: r=A*exp(-E/RT), which all coefficients have been obtained from literature. my problem is :
when I compiled my UDF and loaded successfully, After more than 20,000 iterations , I can not get a convergent solution. by the way , all ds[eqn] in DEFINE_SOURCE are set to zero. can anyone help me ? it is urgent, Big thanks,
alanlove is offline   Reply With Quote

Old   April 10, 2013, 19:54
Smile hi
New Member
Join Date: Apr 2013
Posts: 1
Rep Power: 0
rezaalipour is on a distinguished road
i am working on hybrid rockets and want to have your guidence and help please.
i need your code .
please send me your code friend
rezaalipour is offline   Reply With Quote


Thread Tools Search this Thread
Search this Thread:

Advanced Search
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
Version 15 on Mac OS X gschaider OpenFOAM Installation 113 December 2, 2009 11:23
Combustion problem in STAR CD... help me, please! mrkokoko STAR-CD 1 September 14, 2009 18:00
Problem with Mass source, Momentum source theory diffo Fluent UDF and Scheme Programming 0 August 20, 2009 07:10
Source terms in local coordinate frames CF CFX 2 August 29, 2006 03:30
Combustion Problem chetan shah FLUENT 1 October 17, 2003 13:20

All times are GMT -4. The time now is 23:08.