A journal bearing of 50 mm diameter supports a shaft running at a speed of 320 rpm. A lubricating oil of absolute viscosity of 0.06 kg/m-s is used. The oil is found to operate satisfactorily with a diametral bearing clearance of 0.15 mm and a bearing pressure of 1.5 N/mm. Consider Sommerfeld number as 14.3 x 10°, a constant. (i) If it is necessary to change the speed to 400 r.p.m, determine the pressure at which the bearing should operate. If, when designed for a speed of 320 r.p.m, and pressure of 1.5 N/mm, the clearance had been made 0.12 mm, what change should be made in (ii) the oil?

A journal bearing of 50 mm diameter supports a shaft running at a speed of 320 rpm. A lubricating oil of absolute viscosity of 0.06 kg/m-s is used. The oil is found to operate satisfactorily with a diametral bearing clearance of 0.15 mm and a bearing pressure of 1.5 N/mm. Consider Sommerfeld number as 14.3 x 10°, a constant. (i) If it is necessary to change the speed to 400 r.p.m, determine the pressure at which the bearing should operate. If, when designed for a speed of 320 r.p.m, and pressure of 1.5 N/mm, the clearance had been made 0.12 mm, what change should be made in (ii) the oil?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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