发明名称 |
Supersonic aircraft exhaust noise suppression system |
摘要 |
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.
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申请公布号 |
US5821472(A) |
申请公布日期 |
1998.10.13 |
申请号 |
US19970917010 |
申请日期 |
1997.08.21 |
申请人 |
NORTHROP GRUMMAN CORPORATION |
发明人 |
ZWERNEMANN, GREGORY R. |
分类号 |
F02K1/08;F02K1/34;F02K1/42;F02K1/44;F02K1/50;F02K1/64;(IPC1-7):F02K1/08;B64D33/04 |
主分类号 |
F02K1/08 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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