Ultrasonic oil-film thickness measurement: An angular spectrum approach to assess performance limits (original) (raw)
2007, The Journal of the Acoustical Society of America
The performance of ultrasonic oil-film thickness measurement is explored. A ball bearing (type 6016, shaft diameter 80 mm, ball diameter 12.7 mm) is used with a 50 MHz focused ultrasonic transducer mounted on the static shell of the bearing and focused on the oil film. In order to explore the lowest reflection coefficient and hence the thinnest oil-film thickness that the system can measure, three kinds of lubricant oils (Shell T68, VG15 and VG5) with different viscosities were tested. The results
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