|
[Sponsors] |
false time step implementation for steady state |
|
LinkBack | Thread Tools | Search this Thread | Display Modes |
June 17, 2008, 23:34 |
false time step implementation for steady state
|
#1 |
Guest
Posts: n/a
|
Hello All,
Convergence for the steady state simulations can be obtained by decreasing the 'false time step'. Keeping the default RMS convergence criteria (10^-4) for the steady state simululation, convergence in my simulation became difficult to achieve after a while and hence I changed the 'Timescale Factor' from 1 to 0.01 [in the pannel Solver Control -> Basic Settings -> Convergence Control ->Fluid Timescale Control]. It resulted in decreasing the auto time scale from 2*10^-2 to 2*10^-4 and I achieved the convergence. I do not have a understanding of how the steady solver works (using a 'false' time step)? Could you please help me in understanding the affect/effect of high/low false time step on the accuracy of results. And what convergence criteria should I use for the problems like cyclone? With very kind regards, Kushagra |
|
June 22, 2008, 20:06 |
Re: false time step implementation for steady stat
|
#2 |
Guest
Posts: n/a
|
Hi,
How timestepping works is described in the documentation. As for what convergence criteria you need, that is problem dependant and you should do a sensitivity study to check it. There is also a guide on convergence levels in the documentation. Glenn Horrocks |
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Floating point exception error | Alan | OpenFOAM Running, Solving & CFD | 11 | July 1, 2021 22:51 |
Time step, Number of time step, Maxximum Iterations per time step | sandisk | FLUENT | 0 | July 18, 2011 03:57 |
IcoFoam parallel woes | msrinath80 | OpenFOAM Running, Solving & CFD | 9 | July 22, 2007 03:58 |
False time step factors | Jesper Laursen | Main CFD Forum | 4 | June 4, 2002 05:35 |
unsteady calcs in FLUENT | Sanjay Padhiar | Main CFD Forum | 1 | March 31, 1999 13:32 |