Motion of a solid sphere in a horizontally oscillating liquid

The behaviour of a single dense sphere in a horizontal tube containing an oscillating liquid has been studied experimentally and theoretically. The experiments were carried out using steel, glass and nylon spheres in water or dilute glucose solutions in a 5·08 cm diameter horizontal tube, at oscillation frequencies of 0·4 to 1·3 Hz. The measured amplitude of oscillation of the spheres agreed fairly well with predictions from the equation of motion of the spheres. It was necessary to allow for the rotational inertia of the rolling spheres and quasi-steady drag behaviour was assumed. Solid—solid friction and boundary layer effects were not included in the analysis and were responsible for some deviations between observation and prediction.