3-D Water Flow in Fluent to Evaluate Pressures

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

 September 1, 2009, 15:16 3-D Water Flow in Fluent to Evaluate Pressures #1 New Member   Allen Hammack Join Date: Sep 2009 Posts: 6 Rep Power: 9 I am trying to simulate a water flow, and there are some problems with the pressures and velocity magnitudes. I have one inflow boundary and one outflow boundary. All other surfaces have wall boundary conditions with a specified shear stress of zero in all directions. I am trying to get my reference pressures correct. Therefore, I am running no flow through the model (by specifying zero velocity through my inflow boundary), and the pressures in the flow domain should be hydrostatic. When I look at my results, I am getting velocity magnitudes up to 5 m/s and pressure that are hydrostatic but do not have the correct magnitudes for the given z-location. What can I check to find out what is wrong with my solution? Does my boundary condition setup sound wrong? Any ideas why the velocity magnitudes are so far from the prescribed inflow velocities? Are there any solver options/tolerances I need to be sure to check?

 September 1, 2009, 19:37 #2 Senior Member   Chris Join Date: Jul 2009 Location: Ohio, USA Posts: 169 Rep Power: 9 Have you tried to change your "inflow" and "outflow" boundary conditions to "wall" so that you, essentially, have a tank filled with water (i.e., no flow)? Also, I think you need to turn gravity on if you want to solve a hydrostatic problem (it's off by default.)

 September 1, 2009, 22:41 3-D Water Flow in Fluent to Evaluate Pressures #3 New Member   Allen Hammack Join Date: Sep 2009 Posts: 6 Rep Power: 9 Chris D, Thanks for your reply! Yes, I have tried running a simulation with "wall" boundary conditions for all surfaces. I also have gravity turned on. Another interesting thing I'm finding with my solution is that not only are the pressures not the hydrostatic values that I calculate analytically for the bottom of my flow domain (although I am getting a hydrostatic pressure distribution) the pressures are not constant for the same depths. This leads me to believe that the solver is not converging, but I can't seem to get any better solution behavior with the options I have changed so far. Any suggestions?

 Tags 3-d, fluent, pressure, water

 Thread Tools Display Modes Linear Mode

 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 OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post Navin Sampath FLOW-3D 2 February 26, 2009 11:46 Davy FLUENT 4 October 23, 2006 03:56 Riaan FLUENT 1 January 21, 2005 15:22 paolo FLUENT 1 April 7, 2004 00:38 Ray FLUENT 1 May 24, 2000 16:50

All times are GMT -4. The time now is 15:10.