Unsteady Flow of a Bingham Fluid in a Circular Tube
This Demonstration shows the velocity distribution for the unsteady flow of a Bingham fluid initially at rest in a circular pipe, when suddenly subjected to a constant pressure gradient. Bingham fluids are viscous fluids that require the application of a shear stress exceeding a critical value (the yield stress) to begin flowing.
 R. B. Bird, W. E. Stewart and E. N. Lightfoot, Transport Phenomena, rev. 2nd ed., New York: John Wiley & Sons, Inc., 2006.