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sreenivas July 27, 2010 03:00

Time step size

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.

Thanks in advance

bengy July 27, 2010 04:00


time step x number of time step = physical time


sreenivas July 27, 2010 04:34

Hi Bengy
Thanks for the reply.But my question is what is the time step exactly means?


bengy July 27, 2010 05:08


but you also asked how it is related to physical time:)


sreenivas July 27, 2010 08:43

Y aur true but my primary interest is to know what exactly time step physically means


Maddin July 31, 2010 11:25

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.

bengy July 31, 2010 15:55

correct me if I wrong, but I think that we have to choose time step that courant number is < 7 ( or even 10 - max).


Maddin July 31, 2010 16:30

Lower 1 or when some mesh cells are not good (typical ccm mesh :D) you have to check the other scalars.

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