What formula is Algor using in the background for steady state fluid analysis for a straight pipe with BCs set for known diameter, length, velocity? I'd like to check the results.
Autodesk simulation Multiphysics/fluid flow is based N-S equation, and the basic assumption is incompressible viscous fluid. The background has no difference for straight pipe flow and flow through any other complex fluid domains.
For laminar fluid through straight pipe (Hagen-Poiseuille flow), it has theory result to compare which include velocity profile and pressure drop along the flow direction. Autodesk simulation Multiphysics/fluid flow has very accurate for this benchmark.
Refer to Wikipedia for the theory result http://en.wikipedia.org/wiki/Hagen–Poiseuille_equation, also you can find the example model in our AVE manual and example.
Here are tips if you are interested to check from your side.
(a) Use fully developed result which should has allow contain distance from inlet to compare theory result
(b) For using coarse mesh, remember to compensate the mesh effect to calculate average inlet velocity. The one layer element close to the wall has zero velocity on the wall but specified velocity on the interior nodes.
(c) Check Reynolds number for this internal pipe flow, Hagen-Poiseuille flow theory result is for laminar flow only.