A journal bearing is to be designed for a gear reducer shaft that rotates 1200 rpm and applies a 4.45-kN load to the bearing. Proportions of L/D = 1 are desired. SAE 20 oil is to be used, and the average film temperature is expected to be 60°C. The bearing is to be as small as is consistent with reported current practice.
(a) Determine appropriate values of L and D.
(b) Determine values of c corresponding to the two edges of the optimum zone in Figure 13.13.
(c) Does the value of c for minimum friction satisfy Trumpler's criterion for mini- mum acceptable film thickness?