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

icoLagrangianFoam Drag Force Model

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   November 24, 2010, 22:22
Default icoLagrangianFoam Drag Force Model
  #1
Member
 
Paul Reichl
Join Date: Feb 2010
Location: Melbourne, Victoria, Australia
Posts: 33
Rep Power: 16
preichl is on a distinguished road
Hi All,

I am interested in changing the drag force model used in icoLagrangianFoam. After looking at the source code, and I should state that I am not that familiar with C++ (but I have programmed in C and Fortran), it would appear that all I need to change is the HardBallParticle::updateProperties routine in HardBallParticle.C.
Is this correct? or do I need to make additional changes elsewhere?

Also, what do I need to include in IncompressibleCloud.C so that I have access to the timestep, dt, inside this routine?

Thanks in advance for any advice,

Paul

Last edited by preichl; November 25, 2010 at 01:58.
preichl is offline   Reply With Quote

Old   November 25, 2010, 09:00
Default
  #2
Assistant Moderator
 
Bernhard Gschaider
Join Date: Mar 2009
Posts: 4,225
Rep Power: 51
gschaider will become famous soon enoughgschaider will become famous soon enough
Quote:
Originally Posted by preichl View Post
Hi All,

I am interested in changing the drag force model used in icoLagrangianFoam. After looking at the source code, and I should state that I am not that familiar with C++ (but I have programmed in C and Fortran), it would appear that all I need to change is the HardBallParticle::updateProperties routine in HardBallParticle.C.
Is this correct? or do I need to make additional changes elsewhere?

Also, what do I need to include in IncompressibleCloud.C so that I have access to the timestep, dt, inside this routine?

Thanks in advance for any advice,

Paul
At first: use of that solver is discouraged as the new Kinematic-classes provide a much more elegant framework for Lagrangian particles. Have a look at https://openfoam-extend.svn.sourcefo...agrangianFoam/ for using them in incompressible cases (this works with 1.5 too and with minor modifications should work in 1.6 and 1.6.1 äh 1.7 too)
That way you don't have to modify the existing solver but you just write a new DragModel and link it to your solver (same for injection)

As for the locations of your modifications: you're right. Just there

Which time-step do you mean: the fluid time-step or the particle time-step
gschaider is offline   Reply With Quote

Old   November 25, 2010, 18:36
Default
  #3
Member
 
Paul Reichl
Join Date: Feb 2010
Location: Melbourne, Victoria, Australia
Posts: 33
Rep Power: 16
preichl is on a distinguished road
Thanks Bernhard,

I will try out the channelParticles example. It looks like it may have much of what I want in it already.

I was after both the fluid time step and the particle time step.

After implementing an alternative drag law (most likely via the approach you suggested (i.e. by linking it in)) I would like to add the ability to store/write where the particles hit the walls. I guess I could do this by setting the elasticity of the collision to 0.

Thanks again (for this and for many of your highly practical additions like groovyBC and simpleFunctionObjects).

Paul.
preichl is offline   Reply With Quote

Reply


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
decreaing pressure force in 2phase model michaelzhang FLUENT 0 February 26, 2010 09:27
exporting drag force from fluent fluentguy FLUENT 2 October 27, 2009 15:19
drag coefficient & drag force abhishek.mnit FLUENT 0 April 30, 2009 00:48
Particle drag force RE13 FLUENT 1 February 26, 2008 15:55
Airfoil Drag Force wowakai Main CFD Forum 3 October 13, 1998 20:27


All times are GMT -4. The time now is 23:25.