time step changes with velocity in transient simulations

sandisk · February 5, 2011, 21:30

Do we need to change the time step if we change the velocity of the fluid in the pipe. I am running simulations for slurry flow flow in pipes and I need to see pressure drops for different reynold number. So with a time step for a particular reynolds number, i get my desired results but for a different reynolds number should I change my time step ?

Amir · February 6, 2011, 10:56

Hi sunny,
it's better to have a same relation for your cases. for example dt=0.01*(residence time)
residence time=L/V. by these assumptions you can have reasonable comparison between cases.

February 5, 2011, 21:30	time step changes with velocity in transient simulations	#1
sandisk New Member sunny Join Date: Jan 2011 Posts: 29 Rep Power: 15	Do we need to change the time step if we change the velocity of the fluid in the pipe. I am running simulations for slurry flow flow in pipes and I need to see pressure drops for different reynold number. So with a time step for a particular reynolds number, i get my desired results but for a different reynolds number should I change my time step ?

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February 6, 2011, 10:56		#2
Amir Senior Member Amir Join Date: May 2009 Location: Montreal, QC Posts: 735 Blog Entries: 1 Rep Power: 22	Hi sunny, it's better to have a same relation for your cases. for example dt=0.01*(residence time) residence time=L/V. by these assumptions you can have reasonable comparison between cases.