Pulsatile flow patterns in distensible tubes.

• During the last fifty years a number of physical theories have been proposed in an attempt to describe analytically the behavior of pulsatile flow in the mammalian arterial system. In order to make such an approach to a system of nonuniform, viscoelastic vessels containing a non-Newtonian fluid at all possible, it becomes necessary to introduce simplifying assumptions, the judicious selection of which represents one of the most critical points of departure for any analysis and requires considerable insight into biological phenomena. Womersley's theory, although similar to those developed earlier by Witzig and Lambossy, has been the most widely applied because of its refinements and because he provided the tables necessary for a solution of the linearized Navier-Stokes equations with minimal labor.