MEASUREMENT OF THE LATERAL VELOCITY OF A PARTICLE SEDIMENTING IN A VISCOUS-FLUID BETWEEN 2 CONCENTRIC CYLINDERS

An experimental study has been made on the lateral velocity of a spherical rigid particle sedimenting between two vertical concentric cylinders. The ratios of the particle radius to the distance between two cylinders are in the range of 0.01-0.04 and the particle Reynolds numbers are in the range of 0.06-0.36. It is found that the particle moves to an equilibrium position due to effects of both the inner and outer cylinders. Even when a line, forming a radius of 0.01 times the radius of the outer cylinder, was placed at the axis of the cylinder, the lateral equilibrium position was at a distance from the axis of about 0.3 times the outer cylinder radius. The experimentally determined lateral velocity is found to be in good agreement with the theory.