Determinação experimental de fluxo de potencia em vigas

AUTOR(ES)
DATA DE PUBLICAÇÃO

2000

RESUMO

The objective of this work is to review the mathematical equations involved in the methods of calculation of power flow in beams under bending vibration. Several methods are presented and compared. Some of these methods are traditionally employed and use approximation through finite differences in order to ca1culate power flow. Other methods use parametric models for the same calculations. This paper also presents an alternative formulation for such methods, which is based on an approximation through Unidimensional Regressive Discrete Fourier Series, in order to mo dei the vibration field and compute the power flow in a beam subjected to bending vibration. The evaluation of the various methods is done by comparing the theoretical value of the dispersion relation against the ones obtained through the several implemented techniques. As the internal damping of the beam is very low, the power flow can also be compared with the input power in the system. Such comparisons are made for a simple system composed by a beam under bending vibration, in which one end is excited by an electromagnetic shaker driven by random or sinusoidal force, and the other is partially buried into a sandbox, which simulates a quasi anechoic termination. The comparisons conducted were applied to experimental data as well as to a numerical model which is representative of the experimental system, in order to provide validation of the methods studied

ASSUNTO(S)

vigas ondas elasticas vibração

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