Granular surface flows are common in industrial practice and natural systems, however, theoretical description of such flows is at present incomplete. Two prototype systems involving surface flow are compared: heap formation by pouring at a point and rotating cylinders. Continuum models for analysis of these flows are reviewed, and experimental results for quasi-2D systems are presented. Experi...

Relevance. From the theory of hydrodynamics, it is known about interaction a pair vortices in inviscid fluids. The relevance study conditioned upon presence many studies numerical simulations interactions two or cylinders, but lack research practical installations for observing effects attraction and repulsion fluid media may slow down this area application. Purpose. purpose demonstration possi...

Analytical solutions corresponding to the starting flow of an Oldroyd-B fluid between rotating cylinders are established. If the radius of the inner cylinder tends to zero the flow within a circular cylinder is obtained. The well-known solutions for a Navier-Stokes fluid, as well as those corresponding to a Maxwell fluid and to a second grade one, appear as limiting cases of our solutions. The ...