CFD Online Logo CFD Online URL
Home > Forums > FLUENT

Problems with boundary conditions - velocity and pressure not zero

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Display Modes
Old   April 1, 2011, 09:32
Default Problems with boundary conditions - velocity and pressure not zero
New Member
Mikaela Flodin
Join Date: Feb 2011
Posts: 6
Rep Power: 6
M_Flodin is on a distinguished road
I have a problem with boundary conditions. I have four channels. In the inlet section, two of the channels have an inlet where gas enters, the other two channels are closed (it is a wall). In the outlet section the two channels with open inlets are closed (wall) and the channels with closed inlets are open. It this way the gas enters in the inlet section and then it is forced trough the wall between the channels and exits in the outlet section. A wall-flow system.

The problem is that in the outlet section in the channels that are closed the velocity of the gas should be zero, because I have the boundary condition "wall" here. However, it is not zero, but varies between 1-6 m/s depending on the temperature. What can I do to have zero velocity here?

In the channels in the outlet section that are opend the pressure should be zero since I have atmospheric pressure in the surrounding, and I have put Gauss pressure =0. Neither in this case the boundary conditions are correct. In the outlet channel I have a pressure of approx 700 Pa, in the beginning of the channel, and in the outlet (the end of the channel) I have approx 200 Pa, here it should be zero. What can I do to have a pressure that is zero here?

With kindest regards Mikaela
M_Flodin is offline   Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Wind turbine simulation Saturn CFX 34 October 16, 2014 05:27
Boundary Conditions : Total Pressure or Velocity Gearb0x OpenFOAM Running, Solving & CFD 2 February 28, 2011 22:18
RPM in Wind Turbine Pankaj CFX 9 November 23, 2009 05:05
Convective Heat Transfer - Heat Exchanger Mark CFX 6 November 15, 2004 16:55
what the result is negatif pressure at inlet chong chee nan FLUENT 0 December 29, 2001 06:13

All times are GMT -4. The time now is 06:14.