Exhaust noise reduction system of separated exhaust type turbofan engine

A technology of turbofan engine and noise reduction system, which is applied to machines/engines, jet propulsion devices, etc., can solve the problems of poor mixing effect, reduce exhaust noise, attenuate engine exhaust speed, etc., and achieve low manufacturing and installation costs. , The effect of good noise reduction and simple structure

Inactive Publication Date: 2015-03-11
NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
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  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The patent (US5761900) mentions the exhaust noise reduction technology of the two-pole injection hybrid structure, but increases the length of the engine exhaust nozzle, and is not suitable for a separate exhaust turbofan engine
Patents (US6360528B1, US6487848B2) proposed adding a sawtooth crown structure at the end of the engine exhaust nozzle to strengthen the mixing of the engine jet flow and the external environment airflow, so as to attenuate the exhaust velocity and reduce the exhaust noise. Compared with the lobe mixer , the flow direction vortex strength generated by the sawtooth structure is much weaker, so the effect of strengthening mixing is less
The patent (US6571549B1) conceives a pulse jet generator arranged circumferentially outside the outlet of the nozzle. The generated pulse jet stimulates the engine exhaust jet, attenuates the engine exhaust speed, and achieves the purpose of noise reduction. However, this device increases engine complexity

Method used

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  • Exhaust noise reduction system of separated exhaust type turbofan engine
  • Exhaust noise reduction system of separated exhaust type turbofan engine
  • Exhaust noise reduction system of separated exhaust type turbofan engine

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Embodiment Construction

[0023] figure 1 , figure 2 with image 3 It is an integral structure for reducing exhaust noise of a separate exhaust turbofan engine proposed by the present invention. The connotation outer wall surface 10 and the wall surface of the exhaust rectifying inner cone 5 form a connotation exhaust channel, and the connotation exhaust inlet 7 is connected with the engine turbine outlet, and at the end of the connotation exhaust channel, that is, the inner side of the connotation exhaust outlet 9, a design Connotation cyclone4. Figure 4 , Figure 5 with Image 6 It shows the structure of the exhaust rectification inner cone 5 and the inner swirler 4, and the inner swirler (4) at the end of the inner channel has a certain angle with the central axis of the engine θ , under the action of the internal swirler 4, the connotation exhaust rotates clockwise or counterclockwise relative to the central axis of the engine (clockwise and counterclockwise here are related to the position...

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Abstract

The invention discloses an exhaust noise reduction system of a separated exhaust type turbofan engine, and belongs to the technical field of design of aero-engine exhaust systems and exhaust noise reduction. The exhaust noise reduction system is characterized by being composed of an outer culvert outer wall face (1), outer culvert whirlcones (2), an outer culvert inner wall face (3), inner culvert whirlcones (4), an exhaust rectification inner cone (5), outer culvert exhaust inlets (6), inner culvert exhaust inlets (7), outer culvert exhaust outlets (8), inner culvert exhaust outlets (9) and inner culvert outer wall faces (10). The exhaust noise reduction system is simple in structure and small in influence on engine exhaust performance.

Description

[0001] technical field [0002] The invention relates to a separate exhaust type turbofan engine exhaust noise reduction system, which belongs to the technical field of aeroengine exhaust system design and acoustic noise reduction. Background technique [0003] Under the circumstance that people have increasingly urgent requirements for environmental protection, the International Civil Aviation Organization and governments of various countries have paid more and more attention to the control of civil aircraft noise. Aircraft engine noise is one of the main components of aircraft noise, and jet flow noise is an important component of engine noise, especially in the take-off state. For the aero-engine exhaust system, the active jet noise suppression technology is an important issue in the field of aeroacoustics and aero-engine research. Nozzle jet noise reduction and other aspects have important application background. [0004] Specifically, the aerodynamic noise of a civil ...

Claims

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Application Information

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IPC IPC(8): F02K1/46F02K3/00
Inventor 单勇谭晓茗张靖周
Owner NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
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