A note on the power flowing between two conservatively coupled multi-modal subsystems

Abstract In this note the power flowing between two, point spring coupled, axially vibrating rods under various conditions is examined. These studies have been carried out with Statistical Energy Analysis (SEA) in mind in an attempt to gain understanding of some of the underlying assumptions of that approach. The effects of point versus proportional damping, point versus distributed driving and variations in coupling strength are examined. The differences between the damping models are shown to be slight, provided that the damping remains light, while those for the forcing models are shown to depend on the mode shape functions of the subsystems. These results lend credence to some of the results of SEA, in which light proportional damping and randomly distributed forcing are usually assumed. The variations caused by changes in coupling strength clearly illustrate the transition between “weak” and “strong” coupling commonly discussed in many SEA investigations.