PCWE for FSAI -- Derivation of scalar wave equations for fluid-structure-acoustics interaction of low Mach number flows

This paper presents a novel derivation of the perturbed convective waveequation by utilizing the instantaneous velocity field as the foundation forthe convective operator. This approach holds particular significance in thecontext of modeling fluid-structure-acoustic interaction (FSAI) problems, suchas those encountered in human phonation or systems involving fans with flexibleblades. The derivation is explored through two distinct methodologies: onecommencing from the linearized perturbed compressible equations (LPCE) and theother rooted in the acoustic perturbation equations of variant 2 (APE-2). Thecomparative analysis of these alternative derivations may contribute to a moreprofound understanding of the underlying physics involved in FSI scenarios andaeroacoustics.