Study of the Radiation of Acoustic Sources in a Duct

摘要

the work presented in this paper concerns the study of the radiation of an acoustic source located in a three-dimensional duct, in the presence of a shear flow. Two particular shear velocity profiles have been studied : a linear profile and a turbulent 1/7 th power profile. In a previous paper where a two-dimensional duct was considered, we have presented a new analytical method which consists of dividing the guide into a number of uniform flow layers, where each layer is characterized by a Mach number. The comparison between the results obtained by various authors and ou7rs has enabled the validation of our method. The present work consists of, using modal series, studying the radiation of an acoustic source located under the vehicle floor in order to study the engine noise in the case of a duct in three dimensions.