Accession Number : ADA115783

Title :   Sound Transmission through Ducts and Aircraft Noise Prediction. Volume I. Technical Report.

Descriptive Note : Final rept. 15 May 78-15 May 81,


Personal Author(s) : Schauer,John J ; Datko,John T ; Guyton,Robert W

PDF Url : ADA115783

Report Date : Jan 1982

Pagination or Media Count : 55

Abstract : Aircraft engine acoustical lining impedance models, ray acoustics, hydrodynamic modes, and transient analysis of sound propagation in variable area duct studies were applied to aircraft noise prediction. The effects of several duct lining configurations in a TF33 P5 and a CFM56 engined KC-135B aircraft were predicted. The prediction was based on a model corrected to fit flight noise data and modified by including theoretical duct noise attenuation predictions. The transient solution of variable area ducts permitted the prediction of sound propgation in bullet nose inlets for no low and was moderately successful when a potential flow was included with low Mach numbers. Volume I contains the technical report and analysis. Volume II contains the user's manuals and listings of the computer codes developed. (Author)

Descriptors :   *Sound transmission, *Aircraft noise, *Ducts, *Predictions, Transport aircraft, Inlets, Aircraft engine ducts, Systems analysis, Machine coding, Transients, Manuals, User needs, Variable area nozzles, Models, Propagation, Configurations, Flight, Impedance, Hydrodynamics, Orthogonality

Subject Categories : Transport Aircraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE