Accession Number:

ADA055260

Title:

Initial Investigation of Stationary Hydrofoil Cavitation and Cavitation Noise Scaling.

Descriptive Note:

Technical memo.,

Corporate Author:

PENNSYLVANIA STATE UNIV UNIVERSITY PARK APPLIED RESEARCH LAB

Personal Author(s):

• Thompson,D. E.
• Billet,M. L.

Report Date:

1977-12-16

Pagination or Media Count:

74.0

Abstract:

A series of experiments were conducted in order to determine scaling laws for sheet type surface cavitation and the resulting noise. Four geometrically similar 10.6 percent thick symmetrical Joukowski hydrofoils with chord lengths of 1.5, 3, 6, and 12 inches were tested. Pressure distributions on the two largest hydrofoils were measured at several angles of attack. All noise measurements were made at an attack angle of 70 to produce the desired sheet cavitation. Desinent cavitation numbers were obtained as a function of velocity for each hydrofoil at several angles of attack. The noise resulting from various amounts of cavitation on each hydrofoil was measured. The amount of cavitation was determined by the ratio of cavity length L to chord length c. The relative length Lc was varied from zero to one-third. Noise measurements included directivity patterns and spectra. The variation of cavitation noise with cavitation number, velocity, and Reynolds number was determined. Author

Descriptors:

• *CAVITATION
• *HYDROFOILS
• MEASUREMENT
• PRESSURE
• CALIBRATION
• SOUND PRESSURE
• NOISE(SOUND)

Subject Categories:

• Marine Engineering

Distribution Statement:

APPROVED FOR PUBLIC RELEASE