Adjusting Physical Time Scale Dynamically

zephyrus17 · August 19, 2011, 09:30

How would it be possible for the solver to adjust the Physical Time Scale during the solving dynamically based on the solving iteration number? I got the CEL Expression down to:

Code:

0.3 [m]/ave(Velocity)@Body

But just need a way for it to guess the first (and only the first) iteration step, then let my expression take over.

Any help would be greatly appreciated.

mauricio · August 20, 2011, 20:49

I have done something like that in transitory cases with the timestep... it should be something similar for the timescale. I've nested the "if" functions to make the timestep variable depending on the simulation time. In your case you could try reading the iteration number; if iteration number is==1 then do an expression for guessing the first timescale, else use your dinamyc expression.

the variable for accesing the current iteration number is "citern" so the if expression could be something like:

if(citern=1,<Expression for first timestep>,0.3 [m]/ave(Velocity)@Body)

zephyrus17 · August 21, 2011, 10:28

Oh, good job! Thank you for your help!

August 19, 2011, 09:30	Adjusting Physical Time Scale Dynamically	#1
zephyrus17 New Member Join Date: Sep 2010 Posts: 28 Rep Power: 0	How would it be possible for the solver to adjust the Physical Time Scale during the solving dynamically based on the solving iteration number? I got the CEL Expression down to: Code: 0.3 [m]/ave(Velocity)@Body But just need a way for it to guess the first (and only the first) iteration step, then let my expression take over. Any help would be greatly appreciated.

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August 20, 2011, 20:49		#2
mauricio Member Mauricio Labarca Join Date: Aug 2009 Posts: 35 Rep Power: 16	I have done something like that in transitory cases with the timestep... it should be something similar for the timescale. I've nested the "if" functions to make the timestep variable depending on the simulation time. In your case you could try reading the iteration number; if iteration number is==1 then do an expression for guessing the first timescale, else use your dinamyc expression. the variable for accesing the current iteration number is "citern" so the if expression could be something like: if(citern=1,<Expression for first timestep>,0.3 [m]/ave(Velocity)@Body)

August 21, 2011, 10:28		#3
zephyrus17 New Member Join Date: Sep 2010 Posts: 28 Rep Power: 0	Oh, good job! Thank you for your help!