Inside hydrodynamic journal bearings_____________________?
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Answer: A. the oil film pressure is generated only by the rotation of the journal
Explanation
Inside hydrodynamic journal bearings, the oil film pressure is generated only by the rotation of the journal. The rotating journal drags lubricating oil into a converging wedge, creating high hydrodynamic lifting pressure. This self-generated fluid pressure completely separates the metal journal and bearing surfaces during operation. Hydrodynamic lubrication depends entirely on relative sliding velocity, fluid viscosity, and converging wedge geometry. Journal bearings do not require external high pressure oil pumps once rotational speed is fully established. Eccentric positioning of the rotating shaft inside the bearing clearance space creates the necessary pressure wedge.
Option B describes hydrostatic bearings that require an external high pressure pump to supply lubricant. Option C is incorrect because oil must be supplied to the bearing housing to maintain the lubricating film. Option D is wrong because grease is unsuitable for generating the fluid pressure required in hydrodynamic journal bearings.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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