subcritical OUTLET at free surface channel

imbe88 · July 15, 2014, 04:29

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, 04:40

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, 04:59

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

vonboett · July 15, 2014, 07:14

then you can use kfloras aproach, see post #17

July 15, 2014, 04:40		#2
vonboett Senior Member Albrecht vBoetticher Join Date: Aug 2010 Location: Zürich, Swizerland Posts: 237 Rep Power: 16	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.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
how to capture free surface cells?	MichaelVS	FLUENT	1	June 10, 2015 02:18
determine surface height without input (open channel ; free surface and bottom) given	stefenbink	FLUENT	13	January 2, 2014 13:38
UDF Defining VOF Free Surface at Outlet	Alex	Fluent UDF and Scheme Programming	13	August 8, 2012 16:50
BC for free surface in straightopen channel flow	moon1234	FLUENT	0	March 15, 2010 06:50
pressure outlet (open channel flow)	Willem Brantegem	FLUENT	2	April 4, 2007 02:40

July 15, 2014, 04:29	subcritical OUTLET at free surface channel	#1
imbe88 New Member mattia Join Date: Jun 2014 Posts: 4 Rep Power: 11	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, 04:59		#3
imbe88 New Member mattia Join Date: Jun 2014 Posts: 4 Rep Power: 11	Hi, I know the level of the surface at the downstream. Thank you.

July 15, 2014, 07:14		#4
vonboett Senior Member Albrecht vBoetticher Join Date: Aug 2010 Location: Zürich, Swizerland Posts: 237 Rep Power: 16	then you can use kfloras aproach, see post #17