Acoustic Analysis of Elliptical Cylindrical Mufflers
Mimani, Akhilesh
MUNJAL, MANOHAR LAL
This bookbrief provides comprehensive information on the three-dimensional analysis and design of elliptical cylindrical mufflers for automotive applications. A general solution of the Helmholtz equation in elliptical cylindrical co-ordinates is presented in terms of the Mathieu and modified Mathieu modal functions. This is followed by the first-ever tabulation of the non-dimensional resonance frequencies of the rigid-wall transverse modes for a complete range of aspect ratio of the elliptical geometry. The book then outlines a brief theoretical formulation for characterizing elliptical cylindrical chambers with arbitrary location of the inlet/outlet ports.
The following chapters are devoted to analyzing the Transmission Loss (TL) performance of various elliptical muffler configurations, including long semi-elliptical/circular mufflers. Design guidelines are formulated in terms of optimal port locations for the respective configurations, in particular, for short chambers that yield a broadband TL performance, which is a significant and practically applicable contribution. The analytical framework explains how to exploit the principle of excitation or suppression of certain transverse evanescent modes to achieve, for the first time, a broadband TL performance of short straight-flow/flow-reversal elliptical chambers. Furthermore, a justification is presented for the well-known one-dimensional transverse plane wave theory for short chambers by employing the three-dimensional Green’s function. In summary, this bookbrief offers a one-stop, comprehensive guide for all practicing automotive engineer involved in designing mufflers, for applied mathematicians and physicists studying acoustic wave propagation in elliptical geometries, and for students of engineering acoustics.
- ISBN: 978-981-10-4827-2
- Editorial: Springer
- Encuadernacion: Rústica
- Fecha Publicación: 17/02/2017
- Nº Volúmenes: 1
- Idioma: Inglés