Which of the figures illustrated correctly...

Question 1 of 270705eccefa0bacbc34ba4d4706a

Which of the figures illustrated correctly identifies the position the journal will assume in its bearing after it has attained operating speed? See illustration GS-0121.

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Question 1 of 27070

Which of the figures illustrated correctly identifies the position the journal will assume in its bearing after it has attained operating speed? See illustration GS-0121.

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🔍 Key Concepts

• Hydrodynamic journal bearing – how the oil wedge supports the shaft once it is up to speed • Relationship between direction of rotation and where the thickest and thinnest oil film will be in the clearance space • How the load direction (weight of the shaft/propeller thrust) tends to pull the journal toward one side of the bearing

💭 Think About

• Assume the journal is rotating in the direction of the arrow. As it picks up oil, on which side of the bearing will the pressure (oil wedge) be greatest and best able to support the load? • If the load is acting straight down, will the journal end up sitting at the very bottom of the bearing, or slightly lifted and shifted to one side? In which angular direction relative to the load and rotation will that shift be? • Look at each figure and imagine the oil film thickness all the way around. In which view does the minimum clearance (journal closest to shell) occur where you would expect the highest load to be carried?

✅ Before You Answer

• Identify which side of the bearing (leading or trailing, relative to rotation) should have the minimum oil-film thickness once at operating speed • Check that the journal position you choose would allow an oil wedge to form ahead of the load-carrying region, not directly under the point of minimum clearance • Verify that the selected figure shows the journal displaced in a way that is consistent with a downward load and the given direction of rotation