Prediction of Multitone Sound Radiation from a Circular Duct
Abstract:The paper presents a method of quantitative prediction of sound radiation from a semi-infinite hard-walled circular duct with no mean flow, excited by a multitone, the frequency components of which allow for appearance, apart from the plane-wave, of the higher radial modes. The field analysis has been carried out by means of a model assuming, for each frequency, axisymmetric excitation, equipartition of energy between admissible modes and their relative phases being random. Because of this random phase assumption, a statistical approach to the problem was applied. The formulae for the expected value and the standard deviation for the sound intensity, the mean square pressure, the power-gain function and the power output have been derived. Examples of the probability density function, describing probability of obtaining given value of a measurement, are presented for both single tones and bitones. It is shown that although mean directivity patterns of single tones and bitones are similar, their probability characteristics differ significantly, and there is no simple transition between these two cases in their statistical description. Experimental data show a good agreement with the numerical calculations carried out by means of the model proposed above.
Document Type: Research Article
Publication date: November 1, 1997
More about this publication?
- Acta Acustica united with Acustica, published together with the European Acoustics Association (EAA), is an international, peer-reviewed journal on acoustics. It publishes original articles on all subjects in the field of acoustics, such as general linear acoustics, nonlinear acoustics, macrosonics, flow acoustics, atmospheric sound, underwater sound, ultrasonics, physical acoustics, structural acoustics, noise control, active control, environmental noise, building acoustics, room acoustics, acoustic materials, acoustic signal processing, computational and numerical acoustics, hearing, audiology and psychoacoustics, speech, musical acoustics, electroacoustics, auditory quality of systems. It reports on original scientific research in acoustics and on engineering applications. The journal considers scientific papers, technical and applied papers, book reviews, short communications, doctoral thesis abstracts, etc. In irregular intervals also special issues and review articles are published.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Information for Advertisers
- Terms & Conditions
- Ingenta Connect is not responsible for the content or availability of external websites