CN2072155U

CN2072155U - Spiral type impedance composite silencer

Info

Publication number: CN2072155U
Application number: CN 90200944
Authority: CN
Inventors: 董劲松; 马绍白
Original assignee: CHENGGONG MECHANO-ELECTRONIC REPAIR AND MANUFACTURE FACTORY KUNMING
Current assignee: CHENGGONG MECHANO-ELECTRONIC REPAIR AND MANUFACTURE FACTORY KUNMING
Priority date: 1990-01-19
Filing date: 1990-01-19
Publication date: 1991-02-27

Abstract

The utility model relates to an airstream muffler, particularly an air inlet and outlet airstream muffler of a high and a middle pressure blowers. The utility model provides an impedance composite muffler which has the advantages of wide frequency band for muffling, favorable aerodynamic properties, and favorable effects of muffling. The utility model comprises a casing (1), muffling materials (2) and a frame (6), wherein, the muffling materials (2) are fixed to the inner walls of the casing (1); a helical flow deflector (5) is welded on a core tube (4) which is positioned at an axial central line of a pipeline; the edge of the flow deflector (5) contacts a perforated plate 3. The muffling amount is 25 to 40 dB (A) and the resistance loss is 10 to 25 mm H2 O after the utility model is tested on high-pressure centrifugal blowers in Kunming cigarette factories.

Description

Spiral type impedance composite silencer

The utility model belongs to silencer for gas flow, particularly big-and-middle-sized blower fan intake and exhaust silencer for gas flow.

Baffler is a kind ofly to allow air communication to cross and make the device of acoustic attenuation.It should have bigger sound-damping qualities and have good aerodynamic features (transmission loss is little) in enough wide frequency range.The patent application that Patent Office of the People's Republic of China's utility model patent is announced No. 38 bulletins of the 2nd volume GG86201796 provides a kind of " porous throttling baffler " that is applicable to various gas (vapour) body discharging generation noise occasion, it is by muffler pipe, and porous acoustical panel and conical baffling plate are formed.At the bottom of the awl of porous acoustical panel and conical baffling plate with the airflow direction vertical arrangement, when air communication is crossed acoustical panel and conical baffling plate, a part of static energy of air-flow is consumed in: overcome the resistance of air-flow on acoustical panel, thereby the vortex that frictional force between the air-flow and air-flow form behind acoustical panel reduces the pressure and the flow velocity of exhausting air.This muffler structure is comparatively simple, and the deficiency first is at high temperature, water vapor and quieter material being had in the gas of etch, and working life is shorter; Its two be at the inner-walls of duct reflective sound wave only by air viscosity and transmission of heat decay gradually by absorption of air, but when airspeed is very fast, air density descends to understanding influence erasure effect.

The purpose of this utility model is a kind of noise reduction Bandwidth of design, and high temperature and water vapor etch are had strong resistance to corrosion, and the big flow impedance complex formula baffler that can reduce transmission loss under the erasure effect good prerequisite.

The utility model is realized like this: comprise that the perforated plate 3 uniformly-spaced installed with the rectangle shell fills out the sound-absorbing material 2 of lining at interval at shell 1 inwall and perforated plate 3, and the framework 6 that connects and support above-mentioned parts, it is characterized in that being fixed on the supporting frame 6, and be positioned on the core pipe of rectangular duct longitudinal center line and be welded with helical guide plate 5, guide plate 5 edges and perforated plate 3 are tangent; Above-mentioned baffler, its feature are that also guide plate 5 is vertical with core pipe 4, the two surface plastic spraying processing.And span is 50～80mm between shell 1 and the perforated plate 3, and the aperture of perforated plate 3 is 4～8mm, and heart distance in hole is 5～10mm.

The utility model is a kind of impedance complex formula baffler, and after air-flow entered baffler, air-flow advanced along smooth guide plate 5 rotations of helical; And in the air-flow because eddy current or pressure jump has taken place, the noise sound wave that the gas disturbance is caused, its on the one hand because pipeline section changes continuously, forms different resistance expansion chamber bafflers to the sound wave of different wave length, utilizes simultaneously to crosstalk mutually between the different wave length sound wave or interfere to come sound energy consumption; On the other hand, running into sound wave runs into objects such as guide plate and reflects to tube wall, the short high frequency sound wave of wavelength enters and is fixed on sound-absorbing material on the tube wall, causes that air molecule vibrates its gap in, and a part of acoustic energy makes acoustic attenuation owing to the friction of aperture and viscous are converted into heat energy.The utility model is applicable to Roots's Jaeger blower and high pressure or mesolow centrifugal fan intake and exhaust noise elimination, and effect is obvious.After on probation on the Kunming Cigarette Factory high pressure centrifugal blower fan, sound-damping qualities is that L=25～40dB(A), it is 10～25mmH that resistance decreases ₂O.

Fig. 1 is the utility model master diagrammatic sketch.

Fig. 2 is the utility model side diagrammatic sketch.

Below be embodiment: perforated plate 3 and shell 1 usefulness M6 bolt tightening are on square groove steel frame 6, and framework 6 is used the termination intensity of bolt tightening with strengthened frame 6 again with flange 7.The galvanized sheet of above-mentioned shell 1 usefulness δ=1mm, the thickness δ=2mm of perforated plate 3, the aperture and the hole heart are apart from getting 4mm and 5mm respectively.Spacing is 50mm between perforated plate 3 and the shell 1, and wherein evenly pad has the glass yarn 2 of suitable air gap as sound-absorbing material.Core pipe 4 two ends plugs also are bolted on the Flat Steel Bar of framework 6 center lines with M6.Welded helical guide plate 5 on the core pipe, core pipe 4 is vertical with spiral flow deflector 5, vane thickness δ=3mm, and pitch is 700mm, and guide plate 5 edges and perforated plate 3 are tangent, and core pipe 4 is processed baffler total length 2000mm with the surface plastic spraying of guide plate 5.

Claims

1, big-and-middle-sized blower fan intake and exhaust silencer for gas flow, comprise the perforated plate of uniformly-spaced installing with rectangle shell 13, fill out the sound-absorbing material 2 of lining at inner wall of tube shell, it is characterized in that being fixed on the core pipe 4 of rectangular duct longitudinal center line and be welded with the helical guide plate, guide plate 5 edges and perforated plate 3 are tangent.

2,, it is characterized in that guide plate 5 is vertical with core pipe 4, guide plate 5 and the processing of core pipe 4 surface plastic sprayings according to the described baffler of claim 1.

3, according to the described baffler of claim 1, it is characterized in that spacing is 50～80mm between shell 1 and the perforated plate 3,4～8m is got in the aperture of perforated plate, and heart distance in hole is 5～10mm.