A 6-cm diameter shaft rotates at 3000 rpm in a 20-cm long bearing with uniform clearance of 0.2 mm. At steady operating conditions, both bearing and shaft in the vicinity of the oil gap are at 50°C, and the viscosity and thermal conductivity of lubricating oil are 0.05 N-s/m? and 0.17 W/m-K. By assuming the shaft to have reached peak temperature, and both surfaces still to be maintained at 50°c. Simplify and solve the continuity, momentum and energy equations, determine (a) The maximum temperature of oil (b) The rate of heat transfer to the bearing and shaft (c) The mechanical power wasted by the viscous dissipation in the oil. 30C0 OT6 cm Ds cm 20 cm

A 6-cm diameter shaft rotates at 3000 rpm in a 20-cm long bearing with uniform clearance of 0.2 mm. At steady operating conditions, both bearing and shaft in the vicinity of the oil gap are at 50°C, and the viscosity and thermal conductivity of lubricating oil are 0.05 N-s/m? and 0.17 W/m-K. By assuming the shaft to have reached peak temperature, and both surfaces still to be maintained at 50°c. Simplify and solve the continuity, momentum and energy equations, determine (a) The maximum temperature of oil (b) The rate of heat transfer to the bearing and shaft (c) The mechanical power wasted by the viscous dissipation in the oil. 30C0 OT6 cm Ds cm 20 cm

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.22P

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