Parameter sensitivity of a T-junction sea model; the importance of the internal damping loss factors

For a typical building acoustics configuration, a T-junction of plates formed by a light weight wall placed on a heavy floor, a statistical energy analysis (SEA) model is presented. Only structural systems (i.e., no acoustic wavefields) are considered. Besides bending waves also in-plane waves, quasi-longitudinal and plane transverse waves, in particular, are included in the calculation. A parametric survey is conducted on the T-junction model—for one frequency (1000 Hz) only—in order to find the sensitivity of the SEA model to the inaccuracies of its parameters. It is shown that, when using reverberation time measurements of the plates to determine the internal damping loss factors, the worst case variations of the internal damping loss factors cause variations in the junction dampings of bending waves of about one order higher than any of the other parameters. Therefore, the conclusion is that in cases where the internal damping loss factors are large with respect to the coupling loss factors, it is necessary to obtain more accurate estimates for the internal damping loss factors than are found with simple reverberation time measurements of plates.