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

DPMFoam Lagrangian substep control

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   September 6, 2017, 01:53
Default DPMFoam Lagrangian substep control
  #1
Member
 
Robert
Join Date: Sep 2016
Posts: 32
Rep Power: 10
dussa is on a distinguished road
Hi everyone,

I'm having a bit of trouble figuring out how to control the lagrangian particle substep size in a eularian-lagrangian simulation. The timestep is set for the eularian phase in the controlDict, say 5e-4. If I would like the step size for the lagrangian phase to be 5e-5 is this set in the constant/kinematicCloudProperties at the points shown in bold:

pairCollisionCoeffs
{
pairModel pairSpringSliderDashpot;
pairSpringSliderDashpotCoeffs
{
useEquivalentSize no;
alpha 0.02;
b 1.5;
mu 0.10;
cohesionEnergyDensity 0;
collisionResolutionSteps 100;
};
wallModel wallSpringSliderDashpot;
wallSpringSliderDashpotCoeffs
{
useEquivalentSize no;
collisionResolutionSteps 100;
youngsModulus 1e4;
poissonsRatio 0.23;
alpha 0.01;
b 1.5;
mu 0.09;
cohesionEnergyDensity 0;
};
};



I am suspicious this is not where you specify the lagrangian substeps as they are prescribed twice (once for particle-particle, and once for particle-wall interactions). If anyone has any insights as to if this is correct or not, or where the correct place to specify substep size is, please let me know,

Regards,
Rob
dussa is offline   Reply With Quote

Old   September 6, 2017, 20:07
Default
  #2
Member
 
Robert
Join Date: Sep 2016
Posts: 32
Rep Power: 10
dussa is on a distinguished road
So I've had a bit more looking around and it seems others have had the same question in the past, with one post reporting it as a bug that it was not available to be set: https://bugs.openfoam.org/view.php?id=953

and another post saying that in OpenFOAM-2.0 that automatic time sub-cycling to guarantee stability was added: http://www.openfoam.com/releases/ope...lagrangian.php

I also found another thread where someone was attempting to run DPMFoam and posted a portion of their output (DPMFoam case worked perfectly in the first run but crashes in every subsequent run!!), where it shows that there is something called "move-collide subCycle" when the kinematicCloud is being evolved. I think this might be what I want to change for my simulation, however I still can't figure out where this is done. If anyone has any ideas pleasse let me know.

Rob
dussa is offline   Reply With Quote

Old   September 7, 2023, 17:45
Default
  #3
Member
 
Shah Akib Sarwar
Join Date: Mar 2021
Posts: 41
Rep Power: 5
Shah Akib Sarwar is on a distinguished road
Were you able to figure this out?
Shah Akib Sarwar is offline   Reply With Quote

Reply

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
OpenFOAM - Control and Editing of Lagrangian Output Variables gmag OpenFOAM Programming & Development 1 June 25, 2019 12:29
Monte Carlo Simulation: H-Energy is not convergating & high Incident Radiation volleyHC CFX 5 April 3, 2016 05:41
Problem with an old Simulation FrankW CFX 3 February 8, 2016 04:28
CFX FSI Fatal Error unbanana CFX 0 October 3, 2015 05:57
Match Control and Symmetry Boundary Condtions in a quasi 2D calculation peterputer ANSYS Meshing & Geometry 0 May 15, 2012 08:53


All times are GMT -4. The time now is 08:25.