Abstract
The sound power radiated from the discharge of centrifugal fans of diameters between 3 and 612 inches has been measured as a function of fan dimensions and operating conditions. The measurements were made by arranging the fan under test to discharge into an 11 foot nonreflecting tube in which the static pressure could be controlled. Air was exhausted from the tube through a side port of high acoustic impedance located part way down the tube. The detecting microphone, which is located in the tube between the exit port and the acoustic termination, is out of the air stream and, therefore, not subject to wind noise. The total discharge noise power P in watts in the range 75 to 10 000 cps was found empirically to be given by P = 0.90 × 10−4(D/W) H3 + 5.2 × 10−10(Q5/W4D8), where D and W are the fan diameter and width respectively in inches, H is the static pressure in inches of water, and Q is the air flow in cubic feet per minute. The angular frequency of the fan wheel does not appear explicitly since this quantity is uniquely specified by H, Q, D, and W. Spectral analysis indicates that the power is concentrated primarily at low frequencies. Application of the results of this study to design problems will be discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
