CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Running, Solving & CFD

Combustion

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

Like Tree6Likes

Reply
 
LinkBack Thread Tools Display Modes
Old   September 27, 2006, 03:08
Default I am a beginner of OF,and now
  #61
nishio
Guest
 
Posts: n/a
I am a beginner of OF,and now try to simulate SI engine by using engineFoam.
I want to change equivalenceRatio from 1.0 to 0.8.
And,I changed equivalenceRatioin in "constant/combustionProperties" file.
Could I really change ratio?
I need to change another property?

please help me..
  Reply With Quote

Old   September 27, 2006, 03:31
Default Hi Noriaki, to change the equ
  #62
Member
 
Tommaso Lucchini
Join Date: Mar 2009
Posts: 83
Rep Power: 9
lucchini is on a distinguished road
Hi Noriaki,
to change the equivalence ratio you don't have to change it in the constant/thermophysicalProperties, but you have to change the value of ft in the ./-180 directory. ft is the fuel mass fraction, i.e. fuel/(air+fuel), which you can easily relate with the air/fuel ratio and/or the equivalence ratio.
Bye
Tommaso
lucchini is offline   Reply With Quote

Old   September 27, 2006, 04:34
Default Thank you very much. Noriaki.
  #63
nishio
Guest
 
Posts: n/a
Thank you very much.
Noriaki.
  Reply With Quote

Old   September 27, 2006, 04:39
Default Thank you very much. TO Tomma
  #64
nishio
Guest
 
Posts: n/a
Thank you very much.
TO Tommaso.
  Reply With Quote

Old   September 27, 2006, 05:10
Default I want to change compression r
  #65
nishio
Guest
 
Posts: n/a
I want to change compression ratio.
And I changed stroke and clearance value.
But I could not change the ratio.
I need to change another properties?
Please help me.
  Reply With Quote

Old   September 27, 2006, 06:40
Default Hi Noriaki, How do you chec
  #66
New Member
 
Rikard Mikalsen
Join Date: Mar 2009
Posts: 10
Rep Power: 9
kukikano is on a distinguished road
Hi Noriaki,

How do you check the compression ratio? engineCompRatio? Changing the stroke should be enough. Try (in the directory where your case is):

engineCompRatio . case

(where 'case' would be kivaTest if you run the tutorial)
-- change the stroke in case/constant/engineGeometry
-- run engineCompRatio again and see what happens (something should happen)

You can see how the piston motion is calculated in /home/user/OpenFOAM/OpenFOAM-1.3/src/engine/engineTime/engineTime.C.

Rikard
kukikano is offline   Reply With Quote

Old   September 28, 2006, 02:51
Default Thank you Rikard, I will try
  #67
nishio
Guest
 
Posts: n/a
Thank you Rikard,
I will try it.
  Reply With Quote

Old   September 28, 2006, 02:54
Default Thank you Rikard, I will try
  #68
nishio
Guest
 
Posts: n/a
Thank you Rikard,
I will try it.
  Reply With Quote

Old   September 29, 2006, 06:35
Default Hi Tonnaso, I could not open
  #69
nishio
Guest
 
Posts: n/a
Hi Tonnaso,
I could not open file in the ./-180 directory.
I do not know the reason.
Please tell me.
  Reply With Quote

Old   October 1, 2006, 08:08
Default Hi Everyone. In engineFoam,
  #70
atsushi
Guest
 
Posts: n/a
Hi Everyone.

In engineFoam, we can get "log_summery.-15" file after calculation.
It seems that mean pressure and mean temperature is written in it, but I don't know how calculate mean value.

Weighted mean value or something??

Please someone help me.

Thanks.

Atsushi
  Reply With Quote

Old   October 2, 2006, 08:31
Default Hi Atsushi, The code that w
  #71
New Member
 
Rikard Mikalsen
Join Date: Mar 2009
Posts: 10
Rep Power: 9
kukikano is on a distinguished road
Hi Atsushi,

The code that writes to the logSummary file is found in /home/user/OpenFOAM/OpenFOAM-1.3/applications/solvers/combustion /engineFoam/logSummary.H

The values written to the file are volume-weighted averages, calculated with

field.weightedAverage(mesh.V()).value()

or

sum(field*mesh.V())/sum(mesh.V())

Rikard
kukikano is offline   Reply With Quote

Old   October 2, 2006, 11:15
Default Thank you for your reply, Rika
  #72
atsushi
Guest
 
Posts: n/a
Thank you for your reply, Rikard.

Does it mean that
"add temperature of all cell" / "add volume of all cell" ??

Atsushi
  Reply With Quote

Old   October 13, 2006, 06:07
Default I am the japanese college stud
  #73
nishio
Guest
 
Posts: n/a
I am the japanese college student. Please teach me.
I run the engineFoam now.
I want to put chemistryModel in engineFoam.
should I change engineFoam.C or another files?
please tell me how to this definitely.
thanks..
  Reply With Quote

Old   October 13, 2006, 06:29
Default Hi, what do you want to simu
  #74
Member
 
Tommaso Lucchini
Join Date: Mar 2009
Posts: 83
Rep Power: 9
lucchini is on a distinguished road
Hi,
what do you want to simulate with engineFoam and chemistryModel?
regards
tommaso
lucchini is offline   Reply With Quote

Old   October 13, 2006, 06:32
Default Hi, what do you want to simu
  #75
Member
 
Tommaso Lucchini
Join Date: Mar 2009
Posts: 83
Rep Power: 9
lucchini is on a distinguished road
Hi,
what do you want to simulate with engineFoam and chemistryModel?
regards
tommaso
lucchini is offline   Reply With Quote

Old   October 13, 2006, 06:43
Default Hi, By running the engineFoam
  #76
nishio
Guest
 
Posts: n/a
Hi,
By running the engineFoam,I want to see the CO2,N2,O2 distribution such as the result of dieselFoam.
  Reply With Quote

Old   January 30, 2007, 07:20
Default I try to model premix combusti
  #77
nishio
Guest
 
Posts: n/a
I try to model premix combustion in SI engine. I use kivaTest in the tutorial.
Xi=∑/∑0?
What is Xi?
Help me please.
  Reply With Quote

Old   April 4, 2007, 12:09
Default Hi in a domain of the scale fo
  #78
Member
 
O R
Join Date: Mar 2009
Posts: 50
Rep Power: 9
arkangel is on a distinguished road
Hi in a domain of the scale found in pitzDaily, What are the parameters to be chosen in ignites sites in order to ensure a complete combustion.

All is running stable and then an error
FOAM FATAL ERROR : attempt to use janafThermo<equationofstate> out of temperature range 200 -> 6000;

I saw a lot of people having this error , so far noone has a satisfactory answer

the Courant number is in the range
but b min(b) grows up to O(10^-5) with a combustion progress of 50 or 60 %


any idea to bound b or any possible reason for such error
arkangel is offline   Reply With Quote

Old   May 2, 2007, 09:33
Default I am using dieselEngineFoam.
  #79
Member
 
Tomislav Sencic
Join Date: Mar 2009
Posts: 42
Rep Power: 9
tsencic is on a distinguished road
I am using dieselEngineFoam.

How can I display the rate of heat release?

What are the fields:
dQ
phi
kappa
meshPhi
H

in the time directories?
tsencic is offline   Reply With Quote

Old   May 25, 2007, 07:01
Default Hello everyone, What is the
  #80
atsushi
Guest
 
Posts: n/a
Hello everyone,

What is the difference between 'engineFoam' and 'coldEngineFoam'?

I just want to know what kind of simulations I can do in 'coldEngineFoam'.

Any help will be welcome.
Thanks.

Atsu
  Reply With Quote

Reply

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
combustion model in premixed combustion chamber wuyu FLUENT 7 October 21, 2015 13:18
Hydrogen Air combustion in a combustion chamber popi CFX 7 July 11, 2007 18:40
Sawdust Combustion-Non-premixed Combustion Model Jessy FLUENT 1 June 19, 2007 10:59
combustion in internal combustion engine George Main CFD Forum 0 September 7, 2006 14:41
combustion prasat Main CFD Forum 1 June 16, 2003 13:17


All times are GMT -4. The time now is 06:28.