Effect of the Sign of Ro on the Stability of Stewartson Layers Generated by a Rotating Disc

The effect of the sign of rotation on the stability of the Stewartson layer formed by a rotating disc in a rotating fluid is investigated experimentally and numerically. A discrepancy exists between two earlier studies. Ref. [1] found the sign of Ro to have no influence, while Ref. [2] found a strong asymmetric behaviour. Numerical investigations in Ref. [3] suggested a difference in the boundaries along the disc as a possible cause of the discrepancy between the studies. In the current study experimental work is performed on the large scale facility at the University of Warwick (overall height 5.7m and 1.4 m diameter), with a single disc inside a movable end-wall. The size of the facility allows a much larger height to radius ratio than in previous experiments. A fully automated, traverse mounted 3D PIV system is used to allow data- acquisition over the length of the Taylor column without the need for recalibration. Further numerical work is conducted using the code described in Ref. [3]. REFERENCES: [1] W. G. Fr\"uh,. P.L. Read, J. Fluid Mech., vol. 383, p. 143, 1999. [2] R. Hide, R., C.W. Titman J. Fluid Mech., vol. 29, p. 39, 1967. [3] R. Hollerbach, J. Fluid Mech., vol. 492, p. 289, 2003.