User defined scalar boundary condition

September 19, 2005, 05:09

I have a problem regarding the inlet boundary condition of my scalar. I have an inlet with a periodic velocity, where the velocity first is positive, then negative. While the inlet velocity is positive the scalar has the value 1, but then when the inlet velocity is negative the scalar was first set to 0. It then showed that it is not possible for the scalar to flow back. My idea was then to change the inlet scalar boundary condition to flux during the backward flow phase.

There seems, however, not possible to change from specified value to specified flux during computation, or does anyone know how this can be solved?

Regards: Philip

mlbontbs87 · December 4, 2013, 11:23

I know this was from 8 years ago, but did you ever find a solution to this?

September 19, 2005, 05:09	User defined scalar boundary condition	#1
Philip Guest Posts: n/a	I have a problem regarding the inlet boundary condition of my scalar. I have an inlet with a periodic velocity, where the velocity first is positive, then negative. While the inlet velocity is positive the scalar has the value 1, but then when the inlet velocity is negative the scalar was first set to 0. It then showed that it is not possible for the scalar to flow back. My idea was then to change the inlet scalar boundary condition to flux during the backward flow phase. There seems, however, not possible to change from specified value to specified flux during computation, or does anyone know how this can be solved? Regards: Philip

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December 4, 2013, 11:23		#2
mlbontbs87 New Member David Russ Join Date: Dec 2010 Posts: 5 Rep Power: 16	I know this was from 8 years ago, but did you ever find a solution to this?