Accession Number : ADA118439

Title :   Discrete Frequency Noise and Its Reduction in Small Axial-Flow Fans.

Descriptive Note : Technical memo.,

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK APPLIED RESEARCH LAB

Personal Author(s) : Fitzgerald,James Michael

PDF Url : ADA118439

Report Date : 02 Mar 1982

Pagination or Media Count : 147

Abstract : The discrete frequency noise radiated from representative types of axial-flow fans used in electronic equipment is studied in detail. Narrowband analysis of the discrete frequency noise radiated by these types of fans has been conducted in a free-field environment. The far-field sound pressure level, radiated directivity, and total radiated power of the discrete frequency noise is presented. The influence of operating point on the sound radiated from the fans is determined. The discrete frequency noise dominates the characteristic acoustic spectra at high flow coefficients. (Author)

Descriptors :   *Axial flow fans, *Electronic equipment, Noise reduction, Frequency, Flow noise, Free field, Far field, Interactions, Rotor blades, Nonuniform flow, Flow fields, Modification, Prototypes, Configurations

Subject Categories : Air Condition, Heating, Lighting & Ventilating
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE