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Time step size

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Old   July 27, 2010, 03:00
Post Time step size
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sreenivas
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Hi

Can any body explain me what exactly the time step size in star-ccm means and how it is related to physical time.First time i am simulating transient heat transfer process.

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Old   July 27, 2010, 04:00
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hello,

time step x number of time step = physical time

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Old   July 27, 2010, 04:34
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Hi Bengy
Thanks for the reply.But my question is what is the time step exactly means?

Thanks
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Old   July 27, 2010, 05:08
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hi,

but you also asked how it is related to physical time

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Old   July 27, 2010, 08:43
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Y aur true but my primary interest is to know what exactly time step physically means

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Old   July 31, 2010, 11:25
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Courant number, look at this and you will understand how to chose the time step.
Maybe I'm wrong but I think one timestep is like a steady run of the simulation with the boundary conditions which you have at this time.
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Old   July 31, 2010, 15:55
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correct me if I wrong, but I think that we have to choose time step that courant number is < 7 ( or even 10 - max).

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Old   July 31, 2010, 16:30
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Lower 1 or when some mesh cells are not good (typical ccm mesh ) you have to check the other scalars.
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