Most acoustic imaging methods assume the presence of point sound sources and, hence, fail to correctly estimate the sound emissions of distributed sound sources (such as trailing– edge noise). In this contribution, three integration techniques are suggested to overcome this issue based on models considering a single point source, a line source and several line sources, respectively. Two simulated benchmark cases featuring distributed sound sources are used to compare the performance of these integration techniques with respect to other well–known methods. The considered integration methods provide the best performance in retrieving the source levels and require short computational times. In addition, the presence of unwanted noise sources, such as corner sources in wind–tunnel measurements, no longer affects the results negatively when using the last method. A sensitivity analysis shows that the integration technique based on a line source is robust with respect to the choice of the integration area (shape, position and mesh fineness). Practical recommendations are provided for the application of these methods to experimental cases.
|Title of host publication||Proceedings of the 7th Berlin Beamforming Conference|
|Number of pages||21|
|Publication status||Published - 2018|
|Event||7th Berlin Beamforming Conference - Berlin, Germany|
Duration: 5 Mar 2018 → 6 Mar 2018
Conference number: 7
|Conference||7th Berlin Beamforming Conference|
|Abbreviated title||BeBeC 2018|
|Period||5/03/18 → 6/03/18|
|Other||The objective of the conference is to contribute to the development of beamforming methods with respect to the localization and quantification of sound sources. In addition, the conference provides a platform for the presentation and discussion of practical results from a wide range of specific implementations.|
Beamforming with microphone arrays and related techniques have become standard methods in technical acoustics, proven by an ever increasing number of publications at various acoustic conferences. The methods are used in the highly complex field of aero-acoustics, for the sound source localization on moving vehicles, in technical plants and machinery including the automotive industry. A number of companies are offering commercial beamforming systems. At the same time, a large variety of implementations exist in the academic sector as well as tailor-made solutions for special applications. In order to improve the quantitative analysis of the source distributions, inverse methods are becoming increasingly popular.
BeBeC provides a forum for a vivid exchange of experiences and opinions. Both theoretical and practical work receive a platform. Competing institutions and companies are encouraged to participate. Comparisons with other acoustic methods are welcome.