CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Programming & Development

how to decrease time step based on previous result in openfoam

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

Reply
 
LinkBack Thread Tools Display Modes
Old   September 25, 2013, 05:35
Default how to decrease time step based on previous result in openfoam
  #1
Member
 
Yu CAO
Join Date: May 2013
Posts: 74
Rep Power: 4
cctv is on a distinguished road
Hi
how to decrease time step based on previous result in openfoam? for example, at first, I set deltaT=0.1, and runed to 10, then I want to change deltaT to 0.01, and begin from time 10, what should I do? I changed the deltaT to 0.01 in system/controlDIC, but find it just ran 10 times 10.01,not from 10.01 to 10.10. Is that correct? What should I do?
Thank.
cctv is offline   Reply With Quote

Old   September 25, 2013, 06:31
Default
  #2
Member
 
Yu CAO
Join Date: May 2013
Posts: 74
Rep Power: 4
cctv is on a distinguished road
It seems because of time precision. I am wondering if there are any files except the uniform/time in the output folder would record time precision? I successfully change the deltaT in the same folder, but failed to do so by cp previous result from another folder. I am not sure the reason.
cctv is offline   Reply With Quote

Old   September 26, 2013, 04:21
Default
  #3
Senior Member
 
Joachim Herb
Join Date: Sep 2010
Posts: 289
Rep Power: 9
jherb is on a distinguished road
Please post your system/controlDict. The relevant parameters are startFrom, startTime, stopAt, endTime, deltaT, writeControl and writeInterval. Perhaps also adjustTimeStep.
jherb is offline   Reply With Quote

Old   September 26, 2013, 06:34
Default
  #4
Member
 
Yu CAO
Join Date: May 2013
Posts: 74
Rep Power: 4
cctv is on a distinguished road
Quote:
Originally Posted by jherb View Post
Please post your system/controlDict. The relevant parameters are startFrom, startTime, stopAt, endTime, deltaT, writeControl and writeInterval. Perhaps also adjustTimeStep.
startFrom latestTime;
startTime 0.0;
stopAt endTime;
endTime 2000.0;
deltaT 0.00001;
writeControl runTime;
writeInterval 10;
cycleWrite 1;
writeFormat ascii;
writeCompression uncompressed;
timeFormat general;
timePrecision 8;
cctv is offline   Reply With Quote

Old   September 26, 2013, 17:17
Default
  #5
Senior Member
 
Joachim Herb
Join Date: Sep 2010
Posts: 289
Rep Power: 9
jherb is on a distinguished road
I do not know what cycleWrite means. Otherwise you might want to start from the tutorials, e.g. simpleFoam/motorBike:
Code:
startFrom       latestTime;
startTime 0.0;
stopAt          endTime;
endTime 10.1;
deltaT 0.01;
writeControl    timeStep;
writeInterval   1;
jherb is offline   Reply With Quote

Old   September 27, 2013, 16:56
Default
  #6
Member
 
Yu CAO
Join Date: May 2013
Posts: 74
Rep Power: 4
cctv is on a distinguished road
Quote:
Originally Posted by jherb View Post
I do not know what cycleWrite means. Otherwise you might want to start from the tutorials, e.g. simpleFoam/motorBike:
Code:
startFrom       latestTime;
startTime 0.0;
stopAt          endTime;
endTime 10.1;
deltaT 0.01;
writeControl    timeStep;
writeInterval   1;
Have you tried before?
cctv is offline   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
Superlinear speedup in OpenFOAM 13 msrinath80 OpenFOAM Running, Solving & CFD 18 March 3, 2015 06:36
Moving mesh Niklas Wikstrom (Wikstrom) OpenFOAM Running, Solving & CFD 122 June 15, 2014 06:20
InterFoam negative alpha karasa03 OpenFOAM 7 December 12, 2013 04:41
plot over time fferroni OpenFOAM Post-Processing 7 June 8, 2012 07:56
Upgraded from Karmic Koala 9.10 to Lucid Lynx10.04.3 bookie56 OpenFOAM Installation 8 August 13, 2011 04:03


All times are GMT -4. The time now is 05:50.