At higher flow rates, the streamlines are disrupted by eddies moving in all directions. This is turbulent flow.
Most industrial flows are turbulent , but analytical treatment is complex and difficult.
The goal of this section is to describe turbulence and some of the methods and techniques used to try and understand turbulent flows. Flow Regimes Turbulent eddies form from contact of the fluid with a solid boundary or from two fluid layers moving at different speeds. As these eddies grow, the laminar flow becomes unstable and velocities and pressures in the flowing fluid no longer have constant or smoothly varying values. In pipes, relatively large rotational eddies form in regions of high shear near the pipe wall. These degenerate into smaller eddies as energy is dissipated by action of viscosity.