VELOCITY PROFILE IN VISCOELASTIC FLOW AT THE ENTRY OF A TUBE

[摘要] References(8)Local velocities were measured for the flow of a viscoelastic fluid from a large pipe into a small one (an abrupt contraction with diameter ratio 3.5). Under certain conditions it was found that the velocity field at the entrance was distinctly different from the expected pattern, which would be one of gradually increasing velocity near the centerline. Rather it was found that the centerline velocity at the entrance was larger than the centerline velocity in the developed downstream flow; or, in other words, a pronounced funneling was observed. This is attributed to the elastic behavior of the material.