Presentazioni e Articoli Tecnici

This study involves a comparative analysis focusing on the transmission loss (TL) exhibited by both the Helmholtz resonator (HR) and the quarter-wavelength resonator (QWR). These resonators are designed to attenuate sound energy specifically at their respective resonance frequencies. Employing both analytical and numerical approaches, we predict and assess the HR and QWR performance. In this investigation, the HRs and QWRs are integrated as side branches to a main duct. Furthermore, we explore the influence of mean background flow on the Transmission loss of these resonators. FEM-based COMSOL Multiphysics is used for numerical simulation using the Acoustic Module and the CFD Module. The Pressure Acoustics module in the Frequency Domain is used for the no-flow case, where the mean background flow in the system is solved using the k- turbulence model for different Mach numbers. CFD outputs are coupled to the Linearised Naiver-Stokes model using the Background Fluid flow Coupling Multiphysics feature. The narrow region domain was used in the HR’s neck and the QWR tubes. The numerical explanation also covers the coupling phenomenon arising from the parallel attachment of two or more HRs and QWRs. Utilizing the numerical model makes it feasible to maximize the extent of noise reduction via optimal design. Consequently, this approach effectively minimizes the cost and time required for construction and experimentation.