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http://dx.doi.org/10.5050/KSNVE.2012.22.10.917

A Study on the Errors at the Measurement of Sound Power  

Na, Hae-Joong (Korea textile Machinery Institute)
Lim, Byoung-Duk (School of Mechanical Engineering, Yeungnam University)
Publication Information
Transactions of the Korean Society for Noise and Vibration Engineering / v.22, no.10, 2012 , pp. 917-924 More about this Journal
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
Sound Power; Reverberation Time; Direction Cosine Area; Solid Angle;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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