Transactions of the Korean Society for Noise and Vibration Engineering (한국소음진동공학회논문집)

The Korean Society for Noise and Vibration Engineering (한국소음진동공학회)
권호 표지
DOI QR코드

DOI QR Code

A Study on the Errors at the Measurement of Sound Power

음향파워 측정 시 오차에 대한 고찰

  • Received : 2011.09.23
  • Accepted : 2012.07.09
  • Published : 2012.10.20
Download PDF
⟨ Previous Next ⟩

Abstract

Noise power of large machineries, such as textile looms, winders, and twisting machines, is often measured in a reverberant space because they cannot be installed and operated in an anechoic chamber due to their size, weight, and operating conditions. Factors affecting the measurement error of an in-situ noise power measurement include the nonuniform reverberation time and the direction of sound intensity vector which is usually regarded as normal to the measurement surface. In this study errors due to these factors are estimated with the aid of numerical simulation based on the ray-tracing technique. The averaging of reverberation times measured at several points on the measurement surface is suggested to reduce the errors from nonuniform absorption. Also the direction cosine of each surface element is taken into account, which as a whole is represented as a solid angle of the measurement surface.

Keywords

References

  1. Heinrich Kuttruff, 1973, Room Acoustics(3rd ed.), ch.2, Elsevier Applied Science, London.
  2. Irwin, J. D. and Graf, E. R., 1979, Industrial Noise and Vibration Control, Prentice-Hall, Inc., Englewood Cliffs, New Jersey.
  3. Lee, J. W. and Kwon, Y. P., 2006, Effect of the Measuring Method of Reverberation Time Using Impulse Response Method on the Normalized Impact Sound Pressure Level, Transactions of the Korean Society for Noise and Vibration Engineering, Vol. 16, No. 1, pp. 34-39. https://doi.org/10.5050/KSNVN.2006.16.1.034
  4. KS F 2864 : 2002 Measurement of the Reverberation Time of Rooms with Reference to the other Acoustical Parameters.
  5. KS I ISO 3744 : 2002(2007) Acoustics - Determination of Sound Power Levels of Noise Source Using Sound Pressure - Engineering Method in an Essentially Free Field over a Reflecting Plan.
  6. KS A ISO 3746 : 2002(2007) Acoustics - Determination of Sound Power Levels of Noise Source Using Sound Pressure - Survey Method Using an Enveloping Measurement Surface Over a Reflecting Plane.
  7. KS B ISO 9902-6 : 2009 Textile machinery - Noise test code - Part 6 : Fabric manufacturing machinery
  8. Chun, D. H., Na, H. J. and Lim, B. D., 2006, Noise Source Identification of the Rapier Loom, Proc. of INTER-NOISE06, pp. 1362-1368.
  9. Bies and Hansen, Engineering Noise Control : Theory and Practice, 3rd ed., CRC Press.
  10. LMS, 2005, RAYNOISE Revision 3.1 User Manual, LMS International, LEUVEN, Belgium.
  11. Research Council of Architectural Environment Acoustics, 1992, An Introduction to Architectural Environment Acoustics, Han-mi, Seoul.

Cited by

  1. Measurement of Acoustic Radiation Efficiency of the Submerged Circular Cylindrical Structure in Water Tank vol.25, pp.11, 2015, https://doi.org/10.5050/KSNVE.2015.25.11.747