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time step in free surface problems

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Old   June 21, 2007, 09:18
Default time step in free surface problems
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KtoTo
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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
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Old   June 25, 2007, 05:50
Default Re: time step in free surface problems
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rui
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you'd better not do that. Or you cannot get reasonable free surface results
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Old   June 25, 2007, 08:19
Default Re: time step in free surface problems
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KtoTo
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Why do you think so?
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Old   June 26, 2007, 03:27
Default Re: time step in free surface problems
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murash-v
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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
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Old   June 26, 2007, 07:03
Default Re: time step in free surface problems
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KtoTo
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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.
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