Trouble with hagen-poiseuille flow in fluent
 

Hello there,

I'm just getting started with fluent and I'm having some issues when I try to solve a basic hagen-poiseuille case. Here are my parameters: Pipe diameter: .01m, pipe length: 8m, fluid: water, flowrate: 0.000007854m^3/sec. I'm simply trying to match my analytical answer with what fluent spits out, but the pressure drop that fluent returns is around -81Pa/m while my analytical results are around -32Pa/m. I'm using a laminar model with a mass flow inlet boundary condition without specifying the initial gauge pressure. Thanks in advance for any help!

-Pat

You should work through the issues discussed here first:

http://www.cfd-online.com/Wiki/Ansys..._inaccurate.3F