Accession Number : ADA323864

Title :   Mobility Measurements of a Simulated Semi-Infinite Beam Using a Laser Doppler Velocimeter.

Descriptive Note : Technical memo.,

Corporate Author : DEFENCE RESEARCH ESTABLISHMENT ATLANTIC DARTMOUTH (NOVA SCOTIA)

Personal Author(s) : Gilroy, L. E.

PDF Url : ADA323864

Report Date : MAR 1997

Pagination or Media Count : 23

Abstract : An experiment involving the measurement of the vibratory response of a simulated semi-infinite beam was carried out at the Defence Research Establishment Atlantic (DREA) in support of the Ship Noise Project. The primary purpose of the experiment was to establish whether DREA's laser doppler velocimeter (LDV) would be an adequate tool for such measurements in a larger scale test. Secondary purposes included verification of the power flow finite element analysis method for a simple test case and examination of various damping treatments to determine the most effective. Results of the testing showed that the LDV was an excellent noncontacting sensor for the measurement of low level velocity signals providing that care is taken to check the focus of the laser to insure it maintains a lock' on the target and that the signal is kept at a reasonably small level. The use of DREA's milling table allowed for excellent position control and such a system would be ideal for a larger scale test. Of the various thicknesses of damping material applied, the 3/8" treatment seemed to be the most effective.

Descriptors :   *SHIP NOISE, *LASER VELOCIMETERS, MEASUREMENT, VIBRATION, VERIFICATION, BEAMS(STRUCTURAL), CANADA, DAMPING, DOPPLER SYSTEMS.

Subject Categories : Acoustics
      Marine Engineering
      Infrared Detection and Detectors
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE