CFL number close to free surface

Espen · March 21, 2013, 08:40

Hi,

In my free surface simulation (VOF) I want to plot the maximum CFL number close to the free surface, typically within 2-3 cells (where CFL has to be <1 in order to ensure sharp interface) for each time step. The free surface is changing with time, so the area where maximum CFL is to be extracted from is also changing.

Is there a way to do this relatively easy?

lava12005 · March 21, 2013, 21:41

What I can think of is to create a treshold
Then you can input the function with Volume fraction of water (say your fluid is water).
Then specify the mode to be between, range of maybe something like [0.01, 0.99].
This will give you the free surface containing cells.

From here you can create a report of maximum value with parts the treshold and scalar function of the CFL, doing this will give you the maximum CFL of the cells in the treshold.

Hope it helps

March 21, 2013, 08:40	CFL number close to free surface	#1
Espen New Member Espen Larsen Join Date: Mar 2013 Posts: 2 Rep Power: 0	Hi, In my free surface simulation (VOF) I want to plot the maximum CFL number close to the free surface, typically within 2-3 cells (where CFL has to be <1 in order to ensure sharp interface) for each time step. The free surface is changing with time, so the area where maximum CFL is to be extracted from is also changing. Is there a way to do this relatively easy?

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March 21, 2013, 21:41		#2
lava12005 Senior Member KHB Join Date: Aug 2010 Location: Singapore Posts: 118 Rep Power: 15	What I can think of is to create a treshold Then you can input the function with Volume fraction of water (say your fluid is water). Then specify the mode to be between, range of maybe something like [0.01, 0.99]. This will give you the free surface containing cells. From here you can create a report of maximum value with parts the treshold and scalar function of the CFL, doing this will give you the maximum CFL of the cells in the treshold. Hope it helps