Source–sink flows in a rotating annulus: a combined laboratory and numerical study

Abstract

A general characteristic of rapidly rotating fluids is that accurate experimental measurements can only be made of the main (azimuthal) flow. The secondary flow is then usually deduced from theory, although this is often incomplete in the boundary regions where the secondary flow is of most interest.In this paper we consider the case of source-sink flow between the porous walls of a rapidly rotating annular container and numerically integrate the full equations of motion in order to determine the complete structure of the secondary flow. The results are compared with the (approximate) analytic studies of Hide (1968) and Bennetts & Hocking (1973) to show the differences between the two approaches.A defect of many previous numerical papers has been the inability to check the solution in the nonlinear case. To overcome this, new experimental measurements of the azimuthal velocity profile for a Rossby number of 0·238 have been obtained and these are compared with the numerical results.

Fluidization of nanoagglomerates in a rotating fluidized bed

“…The Rossby and Ekman numbers determine the flow regime within the RFB system; there are five possibilities,12, 20 linear flow (1 ≫ E k 1/4 ≫ Ro ), weakly linear flow (1 ≫ E > Ro ∼ E ), weakly nonlinear flow (1 ≫ E ∼ Ro ), nonlinear flow (1 ≥ Ro ≫ E ) and turbulent flow ( Ro > 1 ≫ E ). As mentioned previously, it is important to note that the geometry of the chamber, that is, the radius and width of the rotating distributor, can change the flow regime because the Rossby and Ekman numbers depend on the dimensions of the chamber.…”

Flow Analysis in a Rotating Container with Axial Injection and Radial Ejection

“…그리고 경계층 내에는 5개의 그리드를 배치할 수 있게 (Fig. 3(c) )인 경우 질량의 이송이 경계층을 통해 이루어진다는 Bennetts & Jackson (14) (1974)의 결과와 일치하는 결과 이다. …”

Theoretical and experimental investigation of the structure of azimuthal source–sink flow in a rotating shallow water layer

“…Main aspects concerned in this respect are global circulations in the atmosphere and ocean, stability of zonal geostrophic flows and their topographic modifications. The frequently exploited method for generating zonal flows in laboratory studies is a combination of source and sink of mass situated around the rotation axis ("source-sink method" [2,[4][5][6][7][8]10,11,[13][14][15]). Radial flows inside a concentric source-sink system are transformed into azimuthal (zonal) ones under the action of Coriolis force.…”

“…[4][5][6][7][8]10,11] and references therein). Since the work by Hide [11], main attention has been directed to flows between two vertical concentric cylinders with source-sink of mass situated on the lateral walls.…”