I am a graduate student creating simulation modules for undergrads. I am trying to setup what should be a simple simulation of 30 m/s flow of air perpendicular to a 19 mm diameter pipe. I have converted to using external flow to remove the need for boundary conditions. I am running as a 2D simulation to reduce computational time. However, I have yet to find a mesh to produces accurate results. Either I get a mesh that produced the correct downstream velocity profile and the wrong pressure profile or the correct pressure profile and correct velocity profile which has a minimum velocity over 10x smaller than measured experimentally. Any suggestions to solve the problem whether mesh or otherwise?