Comparisons of Numerically Predicted and Experimentally Measured Radiated Noisefrom a Ring-Stiffened Cylinder

摘要

Defence Research Establishment Atlantic (DREA), with the assistance of HealthCanada, conducted an experiment involving the measurement of radiated noise from a ring stiffened cylinder subjected to a harmonic load in an anechoic chamber. This experiment was performed to provide validation data for structural acoustics computer codes being developed in house and under contract. These codes are used to predict the vibrations of structures submerged in, or filled with, a dense fluid and to also predict the resulting radiated noise. A subset of these codes, comprising the programs VAST and BEMAP, was used to predict the natural frequencies and radiated noise, on and off resonance, from this cylinder. Comparisons are made between the predicted and measured natural frequencies and radiated noise levels and directivity. Overall, the programs were able to accurately predict both the structural resonances and the radiated noise patterns.