CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Main CFD Forum

simulating a two-phase flow with an external field

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

Reply
 
LinkBack Thread Tools Display Modes
Old   August 8, 2000, 11:44
Default simulating a two-phase flow with an external field
  #1
Yi
Guest
 
Posts: n/a
hi,

Any advice on the modeling and simulation of a gas-solid two-phase flow with an exteral magnetic field? Two-fluid model or Eulerian-Lagrangian model?

By the way, the particles are ferromagnetic.

Thanks.

Yi
  Reply With Quote

Old   August 8, 2000, 21:05
Default Re: simulating a two-phase flow with an external f
  #2
Phan Cong Thuong
Guest
 
Posts: n/a
Hi, I am interested in this problem. I am also reseaching to simulate the two-phase flows. Do you have any document about this, please help me!!!! Thank you very much!!!
  Reply With Quote

Old   August 9, 2000, 05:55
Default Re: simulating a two-phase flow with an external f
  #3
mehdi ben elhadj
Guest
 
Posts: n/a
Hi,

Eulerian-Lagrangian model is a classic one but if you want to do simulation with PHOENICS code for exemple I think that you can start with a Two-fluid model and look for results.

For match informations a bout this problem, you can view documentation of ** US ARMY HEADQUATERS**.
  Reply With Quote

Old   August 9, 2000, 07:30
Default Re: simulating a two-phase flow with an external f
  #4
Yi
Guest
 
Posts: n/a
hi, Phan Cong Thuong

I am just curious about the CFD simulation of a two-phase flow with not only gravity force but also other external force fields. As mentioned in the first post, an external magnetic field will have big influence on the motion of the ferromagnetice particles in the investigated two-phase system. I am wondering what is the main factor to cause the impact. Is it only due to the external force acting on the particles like gravity, or is it also due to the inter-particle forces resulting from the external force field? (Suppose the particle diameter is ~1 mm.) This may be easily illustrated using basic knowledge in physics. Unfortunately, I don't know the answer. Frankly speaking, the posted content is not my work.

I ever worked on CFD simulation of gas-solid two-phase flows two years ago. My interest still lies in CFD, though my current work is mostly related with experimental hydrodynamics. As for any documents, I think you will find many references about multiphase CFD in the literature. However, I did not find relevant contributions on my question. If someone knows, I would appreciate very much for any help.

Good luck.

Yi
  Reply With Quote

Old   August 9, 2000, 07:37
Default Re: simulating a two-phase flow with an external f
  #5
Yi
Guest
 
Posts: n/a
hi, there,

Thanks. If possible, I would use CFX or FLUENT.

I think the underlying physics determines which model is better to do the job. I like two-fluid model, but I have no idea how to use it to simulate a gas-solid system in which inter-particle forces play an important role.

Regards, Yi
  Reply With Quote

Old   August 9, 2000, 10:16
Default Re: simulating a two-phase flow with an external f
  #6
Ken Dulaney
Guest
 
Posts: n/a
I don't know about Fluent, but CFX 4.3 is customizable with user fortran so it can handle just about any type of flow situation if you have the time to write the code. CFX does not have a default model for particle-particle interaction like you described, but a brief review of the available fortran routines shows several that relate to the particle transport model that could possibly be modified to handle your situation.
  Reply With Quote

Old   August 9, 2000, 10:52
Default Re: simulating a two-phase flow with an external f
  #7
Sheng
Guest
 
Posts: n/a
MHD simulation on the two phase system is a difficult topic. As your questioin on the choice of the two-fluid model or Eulerian-Lagrangian model, I do not know the exact your system, just some thoughts:

1, Could the second fluid assum to be the continuous phase? (the two-fluid model will base on two sets of NS equation) I always get a question: why you use continunity equation for the bubble? (gas-lquid plume simulation)

2, How many groups or number particles needed to be calcuated? Then, you can think based on the source of your hardware and software. With limted number of particles, may use Eulerian-Lagrangian. Otherwise, two-fluid is good choice.

3, How about the existed results on the Inter-phase transfer (mass, heat..) in the related fields? The results are about the separated particle-fluid or solid-fluid. Anyway, you should find the source terms on the phase interaction. Hence, previous theortiecal and experimental results are important.

4, If magnetic forces have effect on both liquid and solid particles, it become more hard by use two-fluid simulation since two different source terms should be built in the momentum equation.

5, Will you plan to consider the effect of induced curent?

And more.....

Hope for the help Sheng

it is better first ?

  Reply With Quote

Old   August 9, 2000, 11:12
Default Re: simulating a two-phase flow with an external f
  #8
Yi
Guest
 
Posts: n/a
Answer Q1> Two-fluid Model (TFM) has been acknowledged as a powerful and efficient tool to simulate complicated multiphase flows, especially for engineering applications, though there are some arguments about the physics of TFM. As you said in Q2, if the number of particles is not large, Eulerian-Lagrangian model would be a good choice. It is possible for me to do both.

Answer Q4,5> That's what I want to know and to consider before starting the simulation.

Thanks, Sheng.

Yi

  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
Phase Field modeling in OpenFOAM adona058 OpenFOAM Running, Solving & CFD 24 January 31, 2015 07:01
gas-liquid 2 phase flow in microchannels using VoF LyngHoo FLUENT 1 November 13, 2012 20:01
evaporator design including external flow coprem FLUENT 0 September 26, 2011 04:34
External flow field. Moon FLUENT 3 March 5, 2003 11:32
Two phase flow models Atholl Main CFD Forum 2 May 7, 2002 03:49


All times are GMT -4. The time now is 21:30.