subcritical OUTLET at free surface channel

imbe88 · July 15, 2014, 05:29

Hello, when you have a water outlet with subcritical flow (the upstream level is determined of downstream level), what values you put in U, P_rgh, turbulence and phase fraction?

And when flow is supercritical what values you put?

Thanks, Mattia

vonboett · July 15, 2014, 05:40

Hi, do you know the level of the surface at the downstream, behind your outlet? Or do you want it yust to be equal to whatever surface level you get close to the outlet in your simulation? There are several posibilities, thats why I ask.

imbe88 · July 15, 2014, 05:59

Hi, I know the level of the surface at the downstream.
Thank you.

vonboett · July 15, 2014, 08:14

then you can use kfloras aproach, see post #17

July 15, 2014, 05:40		#2
vonboett Senior Member Albrecht vBoetticher Join Date: Aug 2010 Location: Zürich, Swizerland Posts: 240 Rep Power: 17	Hi, do you know the level of the surface at the downstream, behind your outlet? Or do you want it yust to be equal to whatever surface level you get close to the outlet in your simulation? There are several posibilities, thats why I ask. imbe88 likes this.

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July 15, 2014, 05:29	subcritical OUTLET at free surface channel	#1
imbe88 New Member mattia Join Date: Jun 2014 Posts: 4 Rep Power: 12	Hello, when you have a water outlet with subcritical flow (the upstream level is determined of downstream level), what values you put in U, P_rgh, turbulence and phase fraction? And when flow is supercritical what values you put? Thanks, Mattia

July 15, 2014, 05:59		#3
imbe88 New Member mattia Join Date: Jun 2014 Posts: 4 Rep Power: 12	Hi, I know the level of the surface at the downstream. Thank you.

July 15, 2014, 08:14		#4
vonboett Senior Member Albrecht vBoetticher Join Date: Aug 2010 Location: Zürich, Swizerland Posts: 240 Rep Power: 17	then you can use kfloras aproach, see post #17