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Old   June 23, 2008, 14:52
Default transient timestep ?
  #1
amine
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hi

i think that more the transient timestep is smaller more the solution is converging,but the simulation gave me something else ,where the one with the larger timestep converged better?

any comment , would help me.

thanks
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Old   June 24, 2008, 21:36
Default Re: transient timestep ?
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Glenn Horrocks
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Hi,

This is pretty basic stuff, sounds like you need to read a basics of CFD textbook.

In short, ideally the simulation should converge towards the exact answer as the timestep size goes to zero. In reality, you reduce the timestep until the error is down to an acceptable level.

If your simulation changes significantly with different timestep sizes you need to keep going smaller until it does not change to an accuracy tolerance you are happy with.

Glenn Horrocks
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Old   June 28, 2008, 20:22
Default Re: transient timestep ?
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Dany
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Hey everybody,can i know how to choose the number of time steps plz? thank you in advance
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