Contribuição a teoria e pratica da analise modal acustica experimental / A contribution to the theory and practice of experimental acoustic modal analysis
AUTOR(ES)
Gustavo Dalben Rossetto
DATA DE PUBLICAÇÃO
2001
RESUMO
In the present work, a simple geometry (rectangular shallow cavity) is used to investigate the acoustic modal analysis methodology. Analytical and numerical models are developed for the comparison with the experimental results. Three types of excitation devices were constructed. One based on a shaker-driven piston and the other two using a driver loudspeaker. The first actuator based on a driver loudspeaker is similar to a model developed by an EEC project, where a flexible tube with a socket, instrumented with one microphone, at its termination is used to conduct the sound excitation. The second actuator based on a driver loudspeaker alse uses a flexible tube, but it is instrumented with two microphones in its socket instead of one. The behavior of these last two actuators in terms of volume acceleration (essential in the acoustic modal analysis) and active power (necessary for the Experimental Statistical Energy Analysis) being injected into the medium are investigated. The experimental modal analysis of the rectangular cavity is performed and a method using multi-dimensional spatial Fourier transforms of the array of pressure measurements is proposed for the construction of the partic1e displacement field for acoustic mode shape visualization
ASSUNTO(S)
acustica fourier fourier analysis acoustic analise modal analise de modal analysis
