CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Pre-Processing

Diesel substitute

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

Reply
 
LinkBack Thread Tools Display Modes
Old   March 17, 2010, 05:25
Default Diesel substitute
  #1
sbu
New Member
 
Join Date: Mar 2010
Posts: 5
Rep Power: 7
sbu is on a distinguished road
Hi,

I want to simulate the breakup of diesel droplets and therefore I'm searching for a diesel substitute. Bescause I only focus on breakup, the relevant properties for me are density, viscosity and surface tension.

I already checked the source files of several liquids, but I don't understand how the properties are definded.

Which liquid should I use or can sombody explain me how to find out myself?
sbu is offline   Reply With Quote

Old   March 17, 2010, 11:55
Default
  #2
Senior Member
 
Pauli
Join Date: Mar 2009
Posts: 181
Rep Power: 8
Pauli is on a distinguished road
In SAE paper 1999-01-0528, the authors show n-heptadecane provides the best liquid length match with DF2 data.
Pauli is offline   Reply With Quote

Old   March 17, 2010, 14:32
Default
  #3
sbu
New Member
 
Join Date: Mar 2010
Posts: 5
Rep Power: 7
sbu is on a distinguished road
Hi Pauli, thanks a lot for your answer.

Heptadecance seems to fit quite well here. But the problem is that my droplet temperature should be 293 K, which is a few degrees below the meltingpoint of C17H36.

Further more, heptadecane is not implemented in OF, so that I will probably use hexadecane or tetradecane. I found out that their properties are almost equal to the ones of my diesel (rho=831Kg/m^3, sigma=0.026kg/s^2, mu=0.0023Pas).

However, I still don't know how to compare these values to the ones in OF, just to be sure. I'm looking forward to some help.

Thanks, sbu
sbu is offline   Reply With Quote

Old   March 18, 2010, 06:01
Default
  #4
Super Moderator
 
niklas's Avatar
 
Niklas Nordin
Join Date: Mar 2009
Location: Stockholm, Sweden
Posts: 693
Rep Power: 19
niklas will become famous soon enough
Here's a small utility I use from time to time.
It might be helpful

http://files.nequam.se/liquidProp.tgz

unpack it
go to the liquidProp directory and run 'wmake'
go to the example directory and edit your fuel in constant/thermophysicalProperties

run 'liquidProp -T 350' and it will calculate the density at 350 K.

Add additional info statements in liquidProp.C if you want, it should be obvious how to do it.
niklas is offline   Reply With Quote

Old   March 18, 2010, 19:19
Default
  #5
sbu
New Member
 
Join Date: Mar 2010
Posts: 5
Rep Power: 7
sbu is on a distinguished road
Thank you very much, Mr. Nordin. That program works well.

But I've got a new problem now. I've chosen c14h30 as liquid in the thermophysicalProperties file, but I found out that it is not listed in the thermo.dat list.

I haven't found out much about the thermo.dat file and chemkin readers yet, but I hope that there is a way (which is not too difficult) to add c14h30 to the list.

I would be happy about some support.

Thanks in advance, sbu.
sbu is offline   Reply With Quote

Old   March 19, 2010, 02:49
Default
  #6
Super Moderator
 
niklas's Avatar
 
Niklas Nordin
Join Date: Mar 2009
Location: Stockholm, Sweden
Posts: 693
Rep Power: 19
niklas will become famous soon enough
google 'burcat' or go here directly

http://garfield.chem.elte.hu/Burcat/THERM.DAT

just copy/paste the c4h30 stuff into the therm.dat.

as for the chemistry part, you have to figure that out yourself.
If you want to start with just a global reaction being converted to co2 and h2o,
that should be straightforward to just modify the coefficients for the existing c7h16 example.
niklas is offline   Reply With Quote

Old   March 22, 2010, 19:06
Default
  #7
sbu
New Member
 
Join Date: Mar 2010
Posts: 5
Rep Power: 7
sbu is on a distinguished road
Thank you very much again, Mr. Nordin.

That information helped me a lot, although I couldn't add the c14h30 data to the therm.dat file correctly. I hope to solve this problem soon.

Sincerely yours, sbu.
sbu is offline   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
Diesel fuel combustion Marek CFX 1 November 30, 2008 14:39
want a database file for diesel srinivas FLUENT 0 February 27, 2008 02:15
diesel combustion Marco FLUENT 0 September 14, 2005 08:27
Fuel Modelling in Diesel Engines, what's truth Jo CD-adapco 0 August 18, 2004 13:47
Material closest to diesel Prasad Dudhgaonkar FLUENT 0 June 14, 2004 00:57


All times are GMT -4. The time now is 20:10.