CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   CD-adapco (http://www.cfd-online.com/Forums/cd-adapco/)
-   -   time step in free surface problems (http://www.cfd-online.com/Forums/cd-adapco/56143-time-step-free-surface-problems.html)

KtoTo June 21, 2007 09:18

time step in free surface problems
 
Hi! My question is: I try to solve free surface problem in transient mode and set Time Step in Advanced Transients panel. But when solving STAR-CD decreases this value to obtain correct free surface probably. How can I use greater Time Step? (by changing Courant number, numrer of Cycles?) Thanks

rui June 25, 2007 05:50

Re: time step in free surface problems
 
you'd better not do that. Or you cannot get reasonable free surface results

KtoTo June 25, 2007 08:19

Re: time step in free surface problems
 
Why do you think so?

murash-v June 26, 2007 03:27

Re: time step in free surface problems
 
hi. From what data you done this conclusion? I had often work with free surface and never saw like this. Try to use double precision - it is advice of cd-adapco. Can you answer for me: "From what data you done this conclusion?". You may do it in koi8-r or cp-1251 :)

KtoTo June 26, 2007 07:03

Re: time step in free surface problems
 
Hi, murash-v, if you asked me :), after .pstt file has been loaded, I saw that time of time steps is not equal TimeStep multiplied by time step number but varies at PC will. I try to simulate vibration of cistern with water. I should be able to answer in koi8-r or cp-1251 :), but anybody can take an interest in this problem.

Thanks for answer.


All times are GMT -4. The time now is 14:19.