Abstract
Structural intensity, which was introduced by Noiseux and Pavic in the 1970s, is defined as the instantaneous rate of energy transfer per unit area of structure. The SI field indicates the magnitude and direction of vibratory energy flows at any point in a structure. This paper is concerning instantaneous structural intensity for longitudinal vibration on beam with impedance. The instantaneous structural intensity for longitudinal vibration on beam expressed by product of stress and velocity. Stress is expressed Spatial derivative of displacement, and velocity is time derivative of displacement. Instantaneous structural intensity can make us understand the wave transmission in time, which is thought to be useful for building vibration control measure. The instantaneous structural intensity behavior is summarized. Especially we discuss the change of the intensity due to the attachment of the 1-dof vibration system at one point of the beam.
