13.23 A journal bearing of L = 25 mm, D = 50 mm, and a diametral clearance of 0.05 mm supports a 1800 N load while rotating at 1800 rpm. SAE 10 oil is used, with an average film temperature of 50C. Determine (a) minimum oil film thickness, (b) coefficient of friction, (c) maximum film pressure, (d) angle between load direction and minimum film thickness, (e) angle between load direction and termination of film, (f) angle between load direction and maximum film pressure, (g) total circumferential oil flow rate, and (h) side or leakage flow rate. Would you recommend that a little smaller clearance or a little larger be used? Why? 13.24 Repeat Problem 13.21, using the charts, rather than Petroff's equation, and determine the minimum oil film thickness, ho, for (a) A bearing load of 500 N. (b) A bearing load of 5000 N. Note the comparison with answers obtained to Problem 13.21. [Ans.: (a) 1.02 kW, 3.25 Nm,0.086 mm, (b) 1.26 kW, 4.0 Nm,0.041 mm] [13.21 A journal bearing 120 mm in diameter and 60 mm long has a diametral clearance of 0.20 mm. The journal rotates 3000 rpm and is lubricated with SAE 20 oil at an average temperature of 70C. Using Petroff's equation, estimate the power loss and the friction torque. [Ans.: 1.01 kW, 3.2 Nm]]