COMPARISON OF TWO APPROACHES TO PREDICT INTERIOR NOISE DUE TO FLUCTUATION SURFACE PRESSURE WITH AN IDEALIZED SIDE MIRROR

摘要

The radiated sound pressure level (SPL) from an idealized side mirror under aerodynamic load is calculated by the combination of unsteady incompressible fluid flow analysis and statistical energy analysis (SEA). Wavenumber-frequency spectrum analysis is applied to illustrate the characteristics of fluctuation surface pressure (FSP) of the panel behind the mirror. Two semi-empirical models (Corcos model and Efimtsov model) are used to the extract the convective component of FSP and acoustic component is gained by boundary element method (BEM). The accuracy of results achieved by these two methods are studied in order to seek out which approach is more appropriate to predict radiated SPL excited by aerodynamic load. The difference of diffuse acoustic field (DAF) and propagating wave field (PWF) are also compared. The calculation results show that Corcos model coupled with BEM can produce better result compared with experimental data published in literature.