Applications of airborne path frequency based sub structuring

Airborne path frequency based substructuring (FBS) is a procedure in which airborne subsystems, such as rooms or enclosures, are simulated by transfer functions. These transfer functions may be determined experimentally or via simulation. The connections (i.e., ducts) between acoustic subsystems are modeled using transfer matrix theory, which assumes plane wave propagation. Several applications of this approach are presented in this paper. It is demonstrated that the approach can be used to (1) determine the contribution through each connecting duct, (2) the effect of adding treatments or attenuation elements in these ducts, and (3) to assess the effect of adding Helmholtz resonators or other attenuation elements to the acoustic subsystems or rooms themselves. The primary benefit of the approach is that treatments can be considered in the acoustic subsystem or connections without creating a new model of the system.