Implications of setting operating density (vof)

silent2608 · February 13, 2016, 17:45

Hey,

I'm wondering what are the implications of not being able to set operating density? I'm using a UDF as source term to use a transient gravitation model, which automatically disables operating density option.

I guess I could set gravity in the UI to zero, though.

The purpose of setting operating density has never been truly clear to me, so I guess what I'm really asking is what exacty does the setting mean? I just know that you're supposed to set it to the lighter phase (but only if all phases are incompressible) to prevent density round-off errors (?).

hwet · February 16, 2016, 04:46

I think it adds to the stability of the solution, well if your simulation is stable then dont worry about it 'yet'.

February 13, 2016, 17:45	Implications of setting operating density (vof)	#1
silent2608 New Member Join Date: Nov 2015 Posts: 17 Rep Power: 11	Hey, I'm wondering what are the implications of not being able to set operating density? I'm using a UDF as source term to use a transient gravitation model, which automatically disables operating density option. I guess I could set gravity in the UI to zero, though. The purpose of setting operating density has never been truly clear to me, so I guess what I'm really asking is what exacty does the setting mean? I just know that you're supposed to set it to the lighter phase (but only if all phases are incompressible) to prevent density round-off errors (?).

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February 16, 2016, 04:46		#2
hwet Senior Member Join Date: Mar 2014 Posts: 375 Rep Power: 13	I think it adds to the stability of the solution, well if your simulation is stable then dont worry about it 'yet'.