Analysis of Plug Zones in Steady Flow in Undulating Channels

Undulating channels are important in several industrial applications related to heat transfer and also as a modeling resource for complex flow through pores or fibers. In this paper, flow of a Bingham plastic in an undulating channel is studied. An analytical model is developed which allows to determine the regions in the flow where solid (plug) or quasisolid behavior appears. The parameters considered are the dimensionless yield stress, the channel amplitude and the Reynolds number. A variety of cases are presented, in which the characteristics of the flows are described. The main results are presented by means of the streamlines, isobars, constant shear stress lines, isovelocities, and velocity profiles. Good consistency if found among all variables analyzed.