The New Jersey Institute of Technology's
Electronic Theses & Dissertations Project

Title:	A laboratory and field study of the attenuation of sound intensity using a whistle as the sonic generator
Author:	Kumar, Navneet
View Online:	njit-etd2001-020 (xvi, 86 pages ~ 5.8 MB pdf)
Department:	Department of Chemical Engineering, Chemistry and Environmental Science
Degree:	Master of Science
Program:	Chemical Engineering
Document Type:	Thesis
Advisory Committee:	Hanesian, Deran (Committee chair) Perna, Angelo J. (Committee member) Schuring, John R. (Committee member)
Date:	2001-05
Keywords:	attenuation of sounds intensity power equation
Availability:	Unrestricted
Abstract:	This study investigated the attenuation of sound intensity using a whistle as the sonic generator along with the detailed analysis of all the previous studies. Attenuation of sound in air studies were performed in Otto H. York Center for Environmental Engineering and Science at New Jersey Institute of Technology. Sound attenuation through air was measured by doubling the distance for each of five whistles. It was concluded that Whistle No.5 gives the highest sound intensity of 140.54 dB at a distance of 0.75 ft , the closest distance used for measurement, at a air flow rate of 7.5 SCFM. These data were extrapolated to within one-inch of the whistle and the sound intensity at this distance was about an average of 160.7 dB. The data of sound intensity in decibels versus distance in feet were curve fit using the best-fit curve, Power Equation. It was also concluded that a single whistle produces high sound intensities in comparison to the combination of two whistles.This study investigates the recommendations of previous studies for re-conducting the attenuation of sound focused in an artificial fracture. Previous studies by Zarnetske and Godde recommended that the Bootwala, 2000 field study should be re-conducted with the position of the microphone directed into the fracture using Whistle No. 5. This study has developed the complete procedure and methodology to conduct the above studies in the field. Previous studies should be expanded to give more knowledge from controlled laboratory tests. The work should be expanded to include soil, in addition, to the porous rock slab.