Abstract: Faced with the key problems
of machinery-induced vibration and structure-borne noise when
dynamic machines are mounted on flexible foundations such as
upper floors of factory buildings, the vibration and noise
transmission mechanism and optimal control for the flexible
system are systematically studied by the novel approach of power
flow. A more general system of machinery-isolators-flexible
foundation is modelled. Based on substructure transfer matrix
technique the power flow input and transmitted are formulated in
closed forms, and the effects that the flexibility of foundation
and the asymmetricity of system have upon the power flow
transmission spectra are revealed. Also the inverse problems of
isolation design are discussed by using an optimum method.
Optimum design for a typical example about a force fan mounted
on a concrete building floor is successfully performed to show
that the model is practical, the theory and the optimization
developed are reasonable and effective. Thereby, theoretical
bases for accurate prediction of isolation effectiveness and an
optimum method for practical design of a general flexible
isolation system are provided.
Key words:
Power flow Structure-borne
noise
Flexible subsystems Optimum control
* This project is supported by National Natural Science Foundation of
China. Manuscript received on December 20, 1994
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