Constant mass flux at outlet?

Yeats · September 12, 2016, 09:51

Hello!

The ANSYS CFX solver guide states that a uniform mass flux (rho*velocity=const.) is imposed in the case of a mass flow rate boundary, where the velocity direction is specified as normal to the boundary.

However, this causes some confusion, as a) the mass flux in a generic internal flow geometry is not uniform when plotted and b) I can imagine it causes some unphysical values especially in the near wall flow region, where low velocities occur.

Could anybody elaborate or give an explanation for this?

Many Thanks!

turbo · September 12, 2016, 11:18

Will you share what you read? Upload screen captures. I've never heard of what you said.

September 12, 2016, 09:51	Constant mass flux at outlet?	#1
Yeats New Member Join Date: May 2015 Location: Austria Posts: 4 Rep Power: 10	Hello! The ANSYS CFX solver guide states that a uniform mass flux (rho*velocity=const.) is imposed in the case of a mass flow rate boundary, where the velocity direction is specified as normal to the boundary. However, this causes some confusion, as a) the mass flux in a generic internal flow geometry is not uniform when plotted and b) I can imagine it causes some unphysical values especially in the near wall flow region, where low velocities occur. Could anybody elaborate or give an explanation for this? Many Thanks!

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Wind turbine simulation	Saturn	CFX	58	July 3, 2020 01:13
fluid flow but temperature raises from nowhere?	mxcfd	STAR-CCM+	5	September 16, 2014 05:46
Fixed Outlet Mass Flux boundary condition?	trex930	OpenFOAM Pre-Processing	2	June 30, 2010 21:44
total mass flux correction for compressible fluid?	Francesco Di Maio	Main CFD Forum	0	August 21, 2000 04:23
Constant mass flow rate / choking outlet bounardy condition	Min Zhu	Main CFD Forum	1	September 29, 1998 15:33

September 12, 2016, 11:18		#2
turbo Senior Member Join Date: Jun 2009 Posts: 174 Rep Power: 16	Will you share what you read? Upload screen captures. I've never heard of what you said.