NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Modified shielding jet model for twin-jet shielding analysisAn analytical model to estimate the shielding of noise emitted from a point noise source has been developed assuming the shielding jet to be a cylinder of constant radius with uniform flow across the cross section. Comparison to experiment indicated that the model overestimates diffraction of sound around the jet in the far downstream region. The shielding jet model is modified to include widening downstream of the nozzle exit. This not only represents a more realistic model of the jet, but is also expected to improve the shielding estimate downstream. The modified jet model incorporates a Mach number dependent widening rate, a corresponding decrease in flow velocity downstream and an equivalent slug flow evaluation to retain the locally parallel flow approximation of the model development. The shielding analysis with modified jet model is compared to measured data for a subsonic isothermal air jet and a simulated hot subsonic jet. Improvement of the shielding estimate is discussed.
Document ID
19840047861
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Gerhold, C. H.
(Texas A&M Univ. College Station, TX, United States)
Gilbride, J.
(Texas A&M University College Station, TX, United States)
Date Acquired
August 12, 2013
Publication Date
November 1, 1983
Subject Category
Acoustics
Report/Patent Number
ASME PAPER 83-WA/NCA-2
Accession Number
84A30648
Funding Number(s)
CONTRACT_GRANT: NAG1-11
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available