Abstract
The paper presents the verification of a solution to the narrow sound frequency range problem of flat reflective panels. The analytical, numerical and experimental studies concerned flat panels, panels with curved edges and also semicircular elements. There were compared the characteristics of sound reflected from the studied elements in order to verify which panel will provide effective sound reflection and also scattering in the required band of higher frequencies, i.e. above the upper limit frequency. Based on the conducted analyzes, it was found that among some presented solutions to narrow sound frequency range problem, the array composed of panels with curved edges is the most preferred one. Nevertheless, its reflection characteristic does not meet all of the requirements, therefore, it is necessary to search for another solution of canopy which is effective over a wide frequency range.Keywords:
sound reflection, reflective panels, sound scattering.References
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2. Cox T. J, D’Antonio P. (2004), Acoustic absorbers and diffuser, 2nd edition, Taylor & Francis, London.
3. Kamisiński T., Szeląg A., Rubacha J.(2012), Sound reflection from overhead stage canopies depending on ceiling modification, Archive of Acoustics, 37, 2, 213-218.
4. Kamisiński T., Polaczek A., Rubacha J. (2010), Measurement of parameters of sound reflecting screens, Mechanics and Control, 29, 4, 174–178.
5. Kamisiński T., Burkot M., Rubacha J., Brawata K. (2009), Study of the effect of the orchestra pit on the acoustics of the Krakow Opera Hall, Archives of Acoustics, 34, 4, 481-490.
6. Kamisiński T., Brawata K., Pilch A., Rubacha J., Zastawnik M. (2012), Test Signal Selection for Determining the Sound Scattering Coefficient in a Reverberation Chamber, Archives of Acoustics, 37, 4, 405-409.
7. Rathsam J., Wang L. (2010), Planar reflector panels with convex edge, Acta Acustica United with Acustica, 96, 5, 905-913.
8. Rindel J. H. (1986), Attenuation of sound reflections due to diffraction, Proceedings of Nordic Acoustical Meeting, pp. 257-260, Denmark.
9. Skålevik M. (2007), Low frequency limits of reflector arrays, Retrieved February 12th, 2014, from www.akutek.info.
10. Szeląg A., Rubacha J., Kamisiński T.(2013), Narrow sound frequency range problem of reflector arrays, Acta Phisica Polonica, 123, 6, 1059-1063.
