Acoustics – Sound-modifying means – Muffler – fluid conducting type
Patent
1997-08-21
1998-10-13
Dang, Khanh
Acoustics
Sound-modifying means
Muffler, fluid conducting type
181219, 23926513, F02K 108, B64D 3304
Patent
active
058214720
ABSTRACT:
A method of reducing noise from a jet engine at a distance D from the engine comprising the step of up-shifting frequencies of noise from the jet engine to higher frequencies to cause increased noise fall-off in the distance D. Where the jet engine has an exhaust nozzle for exhaust gases carrying the noise of minimum cross-sectional area A, the method comprises, disposing a frequency shifting plate containing a plurality of small openings therethrough of total cross-sectional area A across the exhaust nozzle and passing all exhaust gases from the jet engine through the frequency shifting plate. Each of the plurality of small openings has an individual cross-sectional area which up-shifts frequencies of noise from the jet engine passing therethrough to higher frequencies. Various embodiments of apparatus to perform the method are disclosed.
REFERENCES:
patent: 3061038 (1962-10-01), Lawler et al.
patent: 3286786 (1966-11-01), Wirt
patent: 3437173 (1969-04-01), Ehrich
patent: 3587973 (1971-06-01), Wolf
patent: 3605939 (1971-09-01), Duthion
patent: 3614037 (1971-10-01), Vdolek
patent: 3710890 (1973-01-01), True et al.
patent: 3721314 (1973-03-01), Hoch et al.
patent: 3974987 (1976-08-01), Shorr
patent: 4091892 (1978-05-01), Hehmann et al.
patent: 4226297 (1980-10-01), Cicon
patent: 4291782 (1981-09-01), Klees
patent: 4353516 (1982-10-01), Soligny et al.
patent: 4509616 (1985-04-01), Blecherman
patent: 4674716 (1987-06-01), Moore
patent: 5154052 (1992-10-01), Giffin, III et al.
patent: 5167383 (1992-12-01), Nozaki
patent: 5463866 (1995-11-01), Klees
Anderson Terry J.
Dang Khanh
Hoch Jr. Karl J.
Northrop Grumman Corporation
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