CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > CFX

LNG BOG Ejector

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   December 2, 2019, 04:14
Default LNG BOG Ejector
  #1
New Member
 
RAVI KARAN TRIPATHI
Join Date: Aug 2014
Posts: 9
Rep Power: 7
xnou is on a distinguished road
Hello everyone,

Could anyone please help me to simulate the LNG BOG Ejector.


Thanks,
Ravi
xnou is offline   Reply With Quote

Old   December 2, 2019, 04:53
Default
  #2
Senior Member
 
Gert-Jan
Join Date: Oct 2012
Posts: 921
Rep Power: 15
Gert-Jan is on a distinguished road
I think no one on this forum knows what a LNG BOG Ejector is..........
Gert-Jan is online now   Reply With Quote

Old   December 3, 2019, 00:58
Default
  #3
New Member
 
RAVI KARAN TRIPATHI
Join Date: Aug 2014
Posts: 9
Rep Power: 7
xnou is on a distinguished road
Hello Jan,

Thanks for reply!!

Ejector is a device in which pumping effect is achieved using motive fluid.

In a jet ejector the static pressure energy of the
motive flow which cannot be directly transferred
is thus converted into kinetic energy. This kinetic
energy can be released to the suction flow
by impulse transfer while both flows mingle.
the diffuser converts the kinetic energy of the
mixture consisting of motive flow and suction
flow back into static pressure energy.

so basically it acts as CD nozzle but having two inlets for different fluids. In my case LNG is entering from one inlet and BOG is entering form the second inlet, and then both the fluid gets mixed and passes through the diffuser section. During the mixing of both fluid phase transferred happens and because of this phase transfer and geometric diffuser section there is pressure rise happened at the diffuser outlet.

i am facing the difficulty in defining the phenomenon for phase transfer.
I have attached "ejector.jpg".

Thanks,

Ravi Karan
Attached Images
File Type: jpg ejector.jpg (41.4 KB, 9 views)
xnou is offline   Reply With Quote

Old   December 3, 2019, 03:32
Default
  #4
Senior Member
 
Gert-Jan
Join Date: Oct 2012
Posts: 921
Rep Power: 15
Gert-Jan is on a distinguished road
Still don't know what BOG is.

Nevertheless, accurate phase transfer in such a system is very difficult. You need to include nucleation, (over)saturation, mass transfer, bubble growth, etc. And all that in a case where total energy is required. This is very difficult.
Since I don't know your background and your starting point, I don't know how to start helping.

Without a decent background, your options are 1) a very simplified case, 2) read a few PhD-thesis and come back in a year or 2, or 3) quit.
Gert-Jan is online now   Reply With Quote

Old   December 3, 2019, 05:28
Default
  #5
New Member
 
RAVI KARAN TRIPATHI
Join Date: Aug 2014
Posts: 9
Rep Power: 7
xnou is on a distinguished road
Hello Jan,

I really appreciate your effort to help me.

Lets move step by step as suggested by you. could you help me how to simulate evaporation of LNG (Liquefied Natural Gas).

Regards,
Ravi
xnou is offline   Reply With Quote

Old   December 3, 2019, 07:19
Default
  #6
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 15,920
Rep Power: 122
ghorrocks is a jewel in the roughghorrocks is a jewel in the roughghorrocks is a jewel in the roughghorrocks is a jewel in the rough
Have a look at the CFX tutorials, available on the ANSYS Customer website. There are no LNG evaporation examples, but there are some phase change examples. If you want an example closer to your exact case contact ANSYS support as they have a wide range of examples so if you talk to them they might be able to give you a starting point.
__________________
Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.
ghorrocks is offline   Reply With Quote

Old   December 4, 2019, 01:57
Default
  #7
New Member
 
RAVI KARAN TRIPATHI
Join Date: Aug 2014
Posts: 9
Rep Power: 7
xnou is on a distinguished road
@ghorrocks, I am discussing with them, even Ansys guys are also figuring out. i got some paper in internet who has done in fluent. will it be possible for you to look into that and guide me.
xnou is offline   Reply With Quote

Old   December 4, 2019, 02:04
Default
  #8
New Member
 
RAVI KARAN TRIPATHI
Join Date: Aug 2014
Posts: 9
Rep Power: 7
xnou is on a distinguished road
Hi Jan,

I am working in CFD domain from last 6-7 years. i have performed many external and internal CFD simulation for HP and LP bypass control valve. recently i have simulated erosion (sand erosion using tabak-off and finnie model in choke valve) and also in wet steam erosion.

but so far i have not work for any phase change simulation.
xnou is offline   Reply With Quote

Old   December 4, 2019, 06:15
Default
  #9
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 15,920
Rep Power: 122
ghorrocks is a jewel in the roughghorrocks is a jewel in the roughghorrocks is a jewel in the roughghorrocks is a jewel in the rough
You are doing a very complex simulation which is going to take a lot of development to get working. So no, I cannot guide you through it as I am a busy person. If you ask a specific question we will try to answer it. But no guarantees as your topic is very specialised.
__________________
Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.
ghorrocks is offline   Reply With Quote

Old   December 4, 2019, 09:14
Default
  #10
Senior Member
 
Gert-Jan
Join Date: Oct 2012
Posts: 921
Rep Power: 15
Gert-Jan is on a distinguished road
And the same applies for me. I am very busy and do not have time to start with you from scratch. Please come with specific questions. Then we can see what we can do.
Gert-Jan is online now   Reply With Quote

Old   December 5, 2019, 03:59
Default
  #11
New Member
 
RAVI KARAN TRIPATHI
Join Date: Aug 2014
Posts: 9
Rep Power: 7
xnou is on a distinguished road
@ghorrocks&Jan, i can understand. will come back with some specific question.
xnou is offline   Reply With Quote

Reply

Tags
cfx multiphase simulation

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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
which solver should be used in simulate LNG gasification yangzhuan OpenFOAM 0 July 27, 2017 05:47
liquid-gas ejector lokooko65@gmail.com Fluent Multiphase 0 April 10, 2017 22:39
Single Phase simulation of an ejector Lexicon FLUENT 3 May 21, 2016 13:59
3D Ejector Thrust Calculation Emmanuel FLUENT 0 April 6, 2007 14:59
Modeling a pulsejet and an ejector Emmanuel FLUENT 0 May 24, 2006 19:53


All times are GMT -4. The time now is 18:00.