Consider a 55-cm-long journal bearing that is lubricated with oil whose viscosity is 0.1 kg/m?s at 20°C at the beginning of operation and 0.008 kg/m?s at the anticipated steady operating temperature of 80°C. The diameter of the shaft is 8 cm, and the average gap between the shaft and the journal is 0.08 cm. Determine the torque needed to overcome the bearing friction initially and during steady operation when the shaft is rotated at 1500 rpm.

Consider a 55-cm-long journal bearing that is lubricated with oil whose viscosity is 0.1 kg/m?s at 20°C at the beginning of operation and 0.008 kg/m?s at the anticipated steady operating temperature of 80°C. The diameter of the shaft is 8 cm, and the average gap between the shaft and the journal is 0.08 cm. Determine the torque needed to overcome the bearing friction initially and during steady operation when the shaft is rotated at 1500 rpm.

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter16: Temperature And The Kinetic Theory Of Gases

Section: Chapter Questions

Problem 8OQ

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