A Sound Intensity Probe with Active Free Field

Kletschkowski, Thomas

doi:10.1007/978-94-007-2537-9_10

Thomas Kletschkowski²

Part of the book series: Intelligent Systems, Control and Automation: Science and Engineering ((ISCA,volume 56))

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Abstract

To avoid the time and cost consuming process of realizing artificial free field conditions by introducing passive damping to the interior (which in addition changes the global characteristic of the investigated enclosure) or the need of sophisticated numerical models required to apply inverse noise source localization techniques such as the IFEM, compare Sect. 7.2 and Chap. 13, a novel sound intensity probe with an active free field (SIAF) was proposed in (Sachau et al. in Schallintensitätsdetektor sowie Verfahren zum Messen der Schallintensität. Patent. DE102004009644A1 22.09.2005, 2005a). This chapter reports on the application of the design methodology for ANC-systems proposed in Chap. 8 to the SIAF design process in which a first specification of the novel sound intensity probe was compiled in two successive design steps. The chapter also includes comments on the functional testing of the first SIAF realization. These experiments were especially focused on free field calibration considering the sound intensity measurements errors discussed in Sect. 4.2.2.

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Notes

1.
This is the main difference between the SIAF approach and active control of duct noise, compare e.g. (Freienstein and Guicking 1996) and (Utsumi 1985), or common sound tubes (with standing wave fields) that are applied to determine material properties, see (EN ISO 10534-2 2001).
2.
In order to avoid mistakes, the subscript s is used to indicate the sample time, whereas the periodic time is indicated by T.
3.
Using a 12 mm spacer for the conventional intensity probe and a spacing of 10 cm for the SIAF, the change of phase over the microphone separation distance was given by ±1° for the conventional probe and by ±8.4° for the SIAF, considering the lowest analyzed frequency. These phase differences are greater than the (assumed) phase mismatch between the microphones of the p-p probes. However, if the SIAF is equipped with a microphone-analyzer combination that is not perfectly calibrated in phase, phase calibration (e.g. by a procedure based on switching the microphones as described in EN ISO 10534-2 2001) is required.
4.
According to (Gade 1982) this sound intensity probe can because of the 12 mm spacer be used in the frequency range 125 Hz<f<5 kHz without causing an error magnitude greater than 1 dB.

References

Crocker MJ, Arenas JP (2003) Fundamentals of direct measurement of sound intensity an practical applications. Acoust Phys 49(2):199–214
Article Google Scholar
DIN 18041 (2004) Hörsamkeit in kleinen bis mittelgroßen Räumen. Deutsche Fassung DIN 18041. DIN Deutsches Institut für Normung e.V., Germany
Google Scholar
EN ISO 10534-2 (2001) Akustik—Bestimmung des Schallabsorptionsgrades und der Impedanz in Impedanzrohren Teil 2: Verfahren mit Übertragungsfunktion (ISO 10534-2:1998). Deutsche Fassung EN ISO 10534-2:2001. DIN Deutsches Institut für Normung e.V., Germany
Google Scholar
Freienstein H, Guicking D (1996) Experimentelle Untersuchung von linearen Lautsprecheranordnungen als aktive Absorber in einem Kanal. In: Proc of DAGA 96, Bonn, Germany, pp 112–113
Google Scholar
Gade S (1982) Sound intensity (theory). Technical Review 3, Brüel & Kjaer, 3–39
Google Scholar
Guicking D, Karcher K (1984) Active impedance control for one-dimensional sound. J Vib Acoust Stress Reliab Des 106:393–396
Google Scholar
Kletschkowski T, Sachau D (2007b) Noise source identification using a sound intensity probe with active free-field. In: Proc of 8th conference on active noise and vibration control methods, Krakow-Krasiczyn, Poland, June 11–14
Google Scholar
Kletschkowski T, Sachau D (2008) Design and calibration test of an active sound intensity probe. Adv Acoust Vib 2008, Article ID:574806
Google Scholar
Sachau D, Drenckhan J, Schäfer I (2005a) Schallintensitätsdetektor sowie Verfahren zum Messen der Schallintensität. Patent. DE102004009644A1 22.09.2005
Google Scholar
Utsumi M (1985) Reduction of noise transmission in a duct by termination impedance control of a sidebranch resonator. J Vib Acoust 123:289–296
Article Google Scholar

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Department of Mechanical Engineering, Mechatronics, Helmut-Schmidt-University/University of the Federal Armed Forces Hamburg, Holstenhofweg 85, Hamburg, 22043, Germany
Thomas Kletschkowski

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Kletschkowski, T. (2012). A Sound Intensity Probe with Active Free Field. In: Adaptive Feed-Forward Control of Low Frequency Interior Noise. Intelligent Systems, Control and Automation: Science and Engineering, vol 56. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-2537-9_10

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DOI: https://doi.org/10.1007/978-94-007-2537-9_10
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-007-2536-2
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