6-70 A 4-cm-diameter shaft rotates at 5200 rpm in a 15-cm-long, 8-cm-outer-diameter cast iron bearing (k 70 W/m-K) with a uniform clearance of 0.6 mm filled with lubricating oil (u 0.03 N-s/m2 andk = 0.14 W/m K). The bearing is cooled externally by a liquid, and its outer surface is maintained at 40°C. Disregarding heat conduction through the shaft and assuming one-dimensional heat transfer,determine (a) the rate of heat transfer to the coolant, (b) the surface temperature of the shaft, and (c) the mechanical power wasted by the viscous dissipation in oil. Treat this problem as parallel flowbetween two large plates with one plate moving at constant velocity and the other stationary.FIGURE P6-705200 rpm4 cm8 cm15 cm

Answered: 6-70 A 4-cm-diameter shaft rotates at…

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

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