the Pressure Driven Flow
 

Hi,

I have a problem about simulating 3D incompressible pipe flow using Fluent. This problem has Poisesuille Solution, but the result from Fluent is much bigger than the analytical solution.

I set up my problem as 3D laminar unsteady solver. The entrance pressure as 150 Pa and the outlet pressure as zero. I used pressure_inlet and pressure_outlet boundaries.

How come this simple problem can not get good result agreed with the analytical solution? I searched this forum, finding that another person called Jeremy who tried to simulate a microchannel asked also simialr question here, can anybody here help me figure out what is wrong in my setting up?

Thanks alot.