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

Time of simulation

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

Reply
 
LinkBack Thread Tools Display Modes
Old   June 7, 2006, 12:15
Default Time of simulation
  #1
HAR
Guest
 
Posts: n/a
According to your experience, how long a simulation can take? I want to know if my computer's performance is normal or I need to get a better one. I am simulating a 3D model of 20,000 cels (Hex), it takes about 4 hours to simulate 10 sec. Is that normal?.

Thanks a lot

Har
  Reply With Quote

Old   June 8, 2006, 01:41
Default Re: Time of simulation
  #2
Gernot
Guest
 
Posts: n/a
Thats not enough Information, which models do you use? ( phases , turbulence , .......... )

  Reply With Quote

Old   June 8, 2006, 01:59
Default Re: Time of simulation
  #3
HAR
Guest
 
Posts: n/a
First of all Thanks for being interested in helping me.

The information is:

Mesh: 20,000 cells (Hex) Cells: 50 mm (edge) Model: Mixture (3 phases) water, air and sand. Viscous model: k-e Solver: Piso. BCs: Inlet (vel inlet), outlet (pressure outlet), top of the tank (outflow). Unsteady flow. Time run: 3 hours (approx) Time of simulation: 10 sec

Specification of the engine: UNIX SERVER (Not personal workstation - this is for the whole university): Quad 3.33 Ghz Intel Xeon 64bit processors with HyperThreading, appearing to be 8 processors, yielding 53162.8 BogoMIPS, 28 Gigs of RAM, and an 29 Gig Swap Partition. THIS IS DIVIDED BY THE NUMBER OF PEOPLE WHO CAN BE SIMULATING AT A TIME.

Thaks for your comments.

Humberto

  Reply With Quote

Old   June 8, 2006, 12:02
Default Re: Time of simulation
  #4
Markus
Guest
 
Posts: n/a
hello HAR

Nice machine you have at your disposal and multiphase problems are perfect canditates for such high end computers. However I hope you are not running in parallel, because for such small grids the data transfer between the processors would detoriate the performance dramatically. It would be intersting to know how many processes are actually running on this machine, what is the time step in your simulation and how many iterations per timestep does it take to reach convergency? Max
  Reply With Quote

Old   June 8, 2006, 16:18
Default Re: Time of simulation
  #5
HAR
Guest
 
Posts: n/a
I use different time steps during the simulation,

A. 0.001 sec, 1000 Steps....then B. 0.004 sec, 1000 steps....then C. 0.007 sec , 700 steps.

Each step has 20 iterations.

Total run time: 3.5 hours.

How is it look?

  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
Multiple floating objects CKH OpenFOAM 10 September 21, 2011 23:13
Total time for simulation Meerkat Main CFD Forum 1 September 5, 2011 07:17
directMapped problem panda60 OpenFOAM Bugs 4 July 8, 2010 10:23
Time step in transient simulation shib FLUENT 0 June 17, 2010 13:07
Differences between serial and parallel runs carsten OpenFOAM Bugs 11 September 12, 2008 11:16


All times are GMT -4. The time now is 12:49.