Ensemble averages of power flow in randomly excited coupled beams

The transmission of transverse vibrational energy between two coupled beams subjected to random excitation is considered. Extensive numerical results are given for the frequency decomposition of power flow between the beams. The power flow is a function of the three non-dimensional parameters describing frequency, ω/ω 1 , where ω 1 is the fundamental resonance frequency of beam one, length ratio, L 2 / L 1 , and damping or modal overlap ratio. Single frequency and octave band averages are shown for various values of L 2 / L 1 , and means and variances are calculated for the ensemble of systems corresponding to a uniform distribution of 1≤ L 2 / L 1 ≤2. Various approximate results based on modal analysis and on SEA are compared with the exact results.