Dh. Fruman et al., ANALYTICAL, NUMERICAL, AND EXPERIMENTAL INVESTIGATION OF THE FLOW STRUCTURE IN A FLOODED BALL-BEARING, Journal of tribology, 118(4), 1996, pp. 865-871
Using an order of magnitude estimate of the lending terms in the equat
ions of motion, the three-dimensional flow in a flooded ball bearing i
s reduced to the investigation of two-dimensional pow problems in a se
ries of bearing cross sections. Combining, through appropriate compati
bility conditions, the individual analytical solutions for the spaces
confined between the cage and the inner wall of the rings, the balls a
nd the rings and the balls and the cage's holes, a very simple analyti
cal model is derived. It allows the computation, in the laminar regime
, of the flow rate, the pressure drop, and the velocity profile in dif
ferent cross sections of the confined spaces. The results of the analy
tical model are confirmed by those obtained using a CFD code and exten
ded to the turbulent regime. The analytical and numerical results are
compared to those obtained from pow visualizations and velocity measur
ements conducted in a specially designed large scale model of a ball b
earing. The agreement is very satisfactory.