## ABSTRACT

This chapter describes the basic concepts of the method of statistical energy analysis (SEA) and presents

its application to structures. The analysis and computation techniques for vibration response and

radiating sound in instruments and structures vary according to the characteristics of the physical

object and the frequency range of interest. Here, we analyze vibration and noise in relation to a rather

large-scale structure over a wide frequency band. Extensive computations are usually required, when,

for example, the ﬁnite element method is used for the computations, with respect to a given oscillation

mode. In particular, when the computations must be performed in the high-frequency range and when

many modes are included in the frequency band, the level of computation becomes considerable,

generally resulting in reduced computational accuracy. To supplement the weak point of the traditional

approach, it is necessary to redistribute statistically the energy equally from all modes in the analytical

frequency band. This allows computed results to be compared with experimental results for a structure

across a wide frequency band. This is the SEA method [1]. Early in its development, the objective of

this analytical method was to predict the vibration response of artiﬁcial satellites and rockets that

receive sound excitation when the jet discharges, and to predict the response of vibration stress in the

boundary layer noise of an aircraft’s airframe. It also became a model that allows an exciting force to be

energy of excitation of a diffused (distributed) sound ﬁeld and its variables that represent the sound

pressure, acceleration, and force. Thus, it can be applied to problems of solid-borne sound in which

vibration propagates through each element [2] and problems of air-borne sound in which multiple

barriers exist [3], even when more excitation points than one are present.