Sound Power Determination based on Minimum Measurement Data using a Three-Dimensional Sound Intensity Measurement System - Experimental Discussion

摘要

In our previous paper, for the sound power determination based on minimum measurement data, if is discussed whether the directivity index can be theoretically calculated from the maximum directivity ratio, the angle of half power, and the surface area of minor lobes using model sound sources. From the results, it can be found that the directivity indices are obtained from five curves (hi models). This report discusses experimentally whether sound power can be measured using the In models obtained from the theoretical discussion by model sound sources. Specifically four machines are selected, and the sound power is measured using the ln models from the search of the peak sound intensity levels, the beam width, and the surface area of minor lobes in an anechoic room. As the results, the minimum number of measurement points is from 2 to 17 for engineering grade sound power determination. It can be said that the proposed searching techniques are effective for sound power determination based on minimum measurement data.