Experimental study of the friction torque on a disc rotating in viscous fluid around its horizontal diameter

Abstract

If a disc is rotated in a fluid around its diameter, a reaction torque arises due to the viscosity of the fluid. In this study, we present the results of an experimental analysis of such a motion. Discs of several diameter have been rotated in water, while the torque and revolutionary speed has been recorded. The data sets are interpreted with the help of dimensionless quantities. Based on the experimental data, analytical formulae are given for the torque-angular velocity relationship and for the critical Reynolds number at which the laminar-turbulent transition occurs.