ANTENNA-WIRE-SUPPORTING BOOMS SUBJECTED TO WIND-INDUCED VIBRATION.
Abstract
Wind-induced vibrations of Wullenwebber antennas and reflector-wire-supporting booms were studied. The objective of the investigations was to develop methods for reducing the high-amplitude vibrations of the booms and the high-band antennas by modifying the existing antenna systems or designing new systems. Instrumented vibration tests were conducted on five existing antenna systems in order to establish the damping factors and natural frequencies of representative antenna booms. Wind tunnel tests were conducted to determine the aerodynamic effect of various configurations of existing booms. Results indicated that sharp corners of rectangular sections and flanges of circular sections have detrimental effects on the aerodynamic responses of the system. Removal of sharp corners or attachment of rounded gloves or fairings on the corners were found to be satisfactory solutions to the problem. Antenna-wire-supporting booms were substituted by equivalent systems of beams on elastic foundations in the analysis for wind loading. Comparisons of various systems were made by varying the stiffness, damping, and the modulus of elastic foundation. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1968
- Accession Number
- AD0675031
Entities
People
- R. H. Chiu
Organizations
- Naval Facilities Engineering Service Center