ENERGY-FLOW VARIABILITY IN A PAIR OF COUPLED STOCHASTIC RODS

Random variations in the transfer functions describing energy flows in a pair of coupled axially vibrating stochastic rods are considered. The material properties of the rods are modelled either as random variables or as random processes, and the consequent effects on the nature of the power receptance functions are studied by using Monte Carlo simulation techniques. The relevance of these results is discussed in the context of variability in average estimates obtained when using Statistical Energy Analysis (SEA) formalisms. The response statistics are shown to vary significantly with the details of the statistical modelling of the system, especially in the low and medium frequency ranges. Moreover, the confidence limits show no tendency to converge toward the mean with increasing frequency. Critical systems the responses of which deviate maximally from the average values are identified and attempts made to understand their nature. © 1993 Academic Press Limited.