a 6cm diameter shaft rotates at 3000rpm in a 20cm - long bearing with a uniform clearance of 0.2mm. At steady operating conditions, both the bearing and the shaft in the vicinity of the oil gap are at 50°c, and the viscosity and thermal conductivity of lubricating oil are 0.05N.s/m^2 and 0.17W/m. k. By simplifying and solving the continuity, momentum, and energy equations, determine: a) the maximum temperature of oil. b) the rate of heat transfer to the bearing and the shaft, and the mechanical power wassted by the viscous dissipation in the oil?

a 6cm diameter shaft rotates at 3000rpm in a 20cm - long bearing with a uniform clearance of 0.2mm. At steady operating conditions, both the bearing and the shaft in the vicinity of the oil gap are at 50°c, and the viscosity and thermal conductivity of lubricating oil are 0.05N.s/m^2 and 0.17W/m. k. By simplifying and solving the continuity, momentum, and energy equations, determine: a) the maximum temperature of oil. b) the rate of heat transfer to the bearing and the shaft, and the mechanical power wassted by the viscous dissipation in the oil?

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 5.50P

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A 6cm diameter shaft rotates at 3000rpm in a 20cm long bearing with a uniform clearance of 0.2mm. At steady operating conditions, both the bearing and shaft in the vicinity of the oil gap are 50°C. The thermal conductivity and the viscosity of the lubricating oil are k=0.17 W/m-K and µ= 0.05 N-s/m2, respectively. By simplifying and solving the differential continuity, momentum and energy equation, determine the maximum temperature of oil. (Hint: Couette flow)
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