Experimental Study on the Velocity Dependent Drag Coefficient and Friction in an Automatic Ball Balancer

  • L. Spannan
  • C. Daniel
  • E. Woschke


The paper presents the evaluation of experiments on the drag and friction forces in an automatic ball balancer, which raceway is embodied by the outer ring of a ball-bearing. Due to the throughout contact between the balls andtheracewaywhileoperatingtheballbalancer,efforthasbeenmadetocharacterisetheflowconditionsofthe surrounding fluid by determining the drag coefficient 𝐶𝐷 as a function of the Reynolds number Re. By the use of fluids with different viscosities and the postulation of continuity in the run of 𝐶𝐷(Re), coefficients for different friction models, e.g. Coulomb friction and rolling friction deduced from Hertzian surface pressure equation can bederived.