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

Simulation stops and starts randomly

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 29, 2017, 03:16
Default Simulation stops and starts randomly
  #1
New Member
 
Karl
Join Date: Jun 2017
Posts: 11
Rep Power: 8
Galactus is on a distinguished road
Greetings Everyone,
I'm using a cluster to run my OpenFoam simulation. I am using
Quote:
mpirun -np 24 pimpleDyMFoam -parallel >& log
Then
Quote:
tail -f log
to keep track of the simulation. But the simulation stops at random places like after the "smooth solver" line and takes lot of time to proceed further only to stop again.

My time steps are in the order of "e-7" and it takes around 5 minutes to reach 1e-4 from 0. Hence it is very fast but stops randomly and takes hours before it continues on its own.

I've previously run a similar case in my PC and did not face any such issue. The only difference between the cluster and PC is that the mesh is much more refined on the cluster.

Any suggestion or tips on how to encounter this issue?
Galactus is offline   Reply With Quote

Old   July 30, 2017, 22:14
Default
  #2
New Member
 
Karl
Join Date: Jun 2017
Posts: 11
Rep Power: 8
Galactus is on a distinguished road
Greetings Everyone,

I let the solver run for 24 hours on the cluster and it stopped at two different places/timesteps (in-between lines smooth solver & GAMG). The report which is generated by the cluster shows a total run time of 24 hours but only 55 minutes of CPU usage time. There was no shortage memory (Hard Disk/Ram) either.

I took the same case and ran it on my PC but with 8 processors and it did not have any issue (though it is slow and is still running). Is there anything extra required to run the program on cluster? The cluster has modules built-in and we can load them to run our programs. Any insight would be appreciated!
Galactus is offline   Reply With Quote

Reply

Tags
cluster computing, log file, openfoam, pimpledymfoam, stop&start

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
foam-extend-4.0 pimpleDyMFoam stops suddenly when running in parallel icab OpenFOAM Running, Solving & CFD 1 May 17, 2017 13:21
Proper settings for PimpleFoam Simulation Mahe88 OpenFOAM Running, Solving & CFD 13 March 16, 2017 12:47
Concentric tubes heat exchanger simulation eliastorca Fluent Multiphase 4 July 2, 2015 05:06
a transient simulation question rystokes CFX 3 June 3, 2009 08:44
case stops when fuel injection starts Antony Siemens 1 August 7, 2005 14:42


All times are GMT -4. The time now is 03:53.