CN2363065Y

CN2363065Y - Multi-way rotary wing type combined noise silencer

Info

Publication number: CN2363065Y
Application number: CN 99230805
Authority: CN
Inventors: 邝勇兴
Original assignee: Li Suiming
Current assignee: Li Suiming
Priority date: 1999-01-19
Filing date: 1999-01-19
Publication date: 2000-02-09
Anticipated expiration: 2009-01-19

Abstract

The utility model relates to the technical field of exhaust airflow silencing of machines or engines. Multi-head rotary wing sheets are used for forming a spiral channel to reduce an exhaust sound wave energy level. The utility model can be widely used for exhaust noise treatment of various centrifugal fans, vacuum pumps, air compressors, etc. The utility model is provided with a circular inner and outer barrel bodies which are concentric, wherein, a coaxial sound absorption column is arranged in the inner barrel body along a length direction; a spiral wing sheet is arranged between the sound absorption column and the inner barrel body; the hollow sound absorption column and the inner barrel body are provided with a plurality of micropores; sound absorption material is filled in a cavity between the outer barrel body and the inner barrel body to cause the length of throughflow to be a plurality of times of outer length of a silencer. Thus noise attenuation values and silencing efficiency can be greatly increased.

Description

Multichannel rotary wing type composite muffler

The utility model relates to the exhaust airstream noise reduction technical field of general machine or motor, particularly a kind ofly constitute the compound silencer that a plurality of spirality channels reduce exhaust sound wave energy level, be widely used in the exhaust sound of all kinds of centrifugal blowers, vacuum pump, air compressor etc. is administered with the bull rotary blade.

Existing silencing apparatus form is a lot, can be divided into three major types by noise elimination mechanism: a class is a dissipative muffler, utilizes sound-absorbing material to eliminate the noise.After sound wave entered silencing apparatus, sound wave contacted with sound-absorbing material, and the resistance of sound-absorbing material and viscous force make a part of acoustic energy turn to heat energy, reach the noise elimination purpose, existing tubular type (comprising circle, rectangle), chip, folded plate type, honeycomb, acoustic streaming formula, cell-type etc.Second class is a reactive muffler, and it by the appropriate combination of different acoustic resistances, acoustic compliance, acoustical mass in the silencing apparatus, makes acoustic energy partly feed back to sound source based on acoustic-electric source ripple principle, or absorbs significantly, thereby reaches the noise elimination purpose; Existing expanding, resonance type, interference type, micropore template etc.The 3rd class is an impedance complex formula silencing apparatus, it is that two kinds of form acoustic wave filter structures of impedance are combined, usually resistance partly is placed on front end, the resistive rear end that is placed on, make the noise reduction frequency that control preferably all be arranged in from the low frequency to the high-frequency range, the silencing apparatus of forms such as existing expansion-resistive, resonance-resistive, expansion-resonance-resistive.

Because the noise elimination value is directly proportional with resistance, i.e. it is one group of contradiction that the increase of noise elimination value and resistance reduce.When sound deadening capacity increases, the volume of silencing apparatus, length, progression all will obviously increase.Existing silencing apparatus isometrical, isometric, etc. under the through-flow condition acoustic reflection and air-flow contact useful area not high, thereby noise attentuation value and acoustical absorptivity are all lower; Complex muffler is resistive and the simple superposition reactive muffling structure is connected, and acoustical absorptivity is also lower.Moreover, general silencing apparatus length is substantially equal to through-flow length (being effective length), through-flow length is the key factor of noise attentuation value, waiting under the flow area condition, not increasing silencing apparatus length increases substantially through-flow length then to make the noise attentuation value to improve, existing silencing apparatus is subjected to conditionalities such as windage and apparent size, and through-flow length is difficult to a times above the outer length of silencing apparatus.

The purpose of this utility model provides a kind of multichannel rotary wing type composite muffler, and under the certain situation of silencing apparatus outward appearance length, it can make through-flow length is the several times of the outer length of silencing apparatus, thereby noise attentuation value and elimination efficiency are increased substantially.

The utility model reaches by following technical measures: the silencing apparatus that model utility proposes, by circular and concentric inside and outside cylindrical shell, spiral fin, compositions such as sound absorbing material, the two ends of cylindrical body are connected with tubular air inlet section and taper type rectification exhaust section by flange respectively, have along its length in the inner barrel between a coaxial sound absorbing post sound absorbing post and the inner barrel and be furnished with spiral fin, all have numerous micropores on hollow sound absorbing post and the inner tube wall, be filled with sound absorbing material in the cavity between outer cylinder body and the inner barrel.

Described sound absorbing post two ends are connected with the reflector and the deflector of taper respectively.

The fin of arranging along the sound absorbing post length direction in the described inner barrel is a single-screw formula or how spiral, along the circumferential direction can the fin sub-multiple angle Divide equally, N represents the fin number in the formula.

But the discontinuous shape of described spiral fin short limb, the continuous shape of the long wing or sandwich-type fin.

The utility model is described in further detail below in conjunction with embodiment and accompanying drawing thereof

Fig. 1 is a structural representation sketch of the present utility model.Fig. 2 is the A-A cut-away view among Fig. 1.

As shown in the figure, this device is to be made of coaxial outer cylinder body 5 and inner barrel 7, is filled with sound absorbing material 6 between inside and outside cylindrical shell, movement-less part in the cylindrical shell.The hollow sound absorbing post 8 of the numerous micropores of surface distributed is set in the inner barrel, be furnished with in the cavity between sound absorbing post and the inner barrel three each other in succession 120 the degree spiral fins 11, fin constitutes air chamber with inner barrel that is distributed with numerous micropores and sound absorbing post, air-flow is under the guide functions of helical, form multichannel spiral forward travel state, receive significant reduction noise, reduce the effect of polluting.

The helical pitch of helical is optionally selected, and is waiting under the flow area, and helical pitch has determined the flow process of spiral air flow.A plurality of spiral wing plates etc. helical pitch, equal helix angle have constituted a plurality of flow spiral passages, adjust helical pitch and can adjust resistance, air-flow flow process and reflective surface angle.

In the tubular suction port 2 and truncated cone relief opening 10 that taper reflector 3 that install at the sound absorbing post two ends and deflector 9 lay respectively at silencing apparatus, the inlet and outlet mouth all links to each other with silencer cylinder by flange 4.The suction port place has the conduit 1 of insertion to communicate with the outlet pipe of gas outlet means.

The noise-cancelling theory of this device: when the air communication of equipment such as centrifugal blower, air compressor discharge is crossed tracheae, there are air motion and acoustic wave movement, air motion can make a part of sound wave (as the flow perturbation sound wave) motion change, and acoustic wave movement can be ignored substantially to the influence of air motion usually.To nonporous solid, air-flow does not have penetrating power, and sound wave has penetrating power, because the feature of mechanical compressional wave, sound wave can produce refraction, scattering and radiation, and not as water and the similar water conservancy diversion of gas, based on above-mentioned analysis, the applicant utilizes spiral motion principle and huyghens principle, designed air-flow be easy to by and sound wave be difficult to by, and the noise elimination structure that repeatedly is refracted, absorbs, decays.

After sound wave enters silencing apparatus,, decayed through 2 expansions of pipeline shape suction port section and 3 reflections of taper reflector and interference; Continue it, in the cylindrical shell of fin is housed, air-flow advances under the water conservancy diversion of spiral fin, sound wave and inner tube wall, fin and sound absorbing post friction make a part of acoustic energy be converted into heat energy on the one hand, resolve into numerous new point source of sound to the four sides diffusion through micropore effect sound wave on the other hand, be delivered to cavity and absorbed some by sound-absorbing material; Moreover continuous helical makes sound wave form continuous radiation sound wave group and air carrier sound wave group and transmit wave group and forms the situation of constantly interfering mutually, thereby sound wave is constantly decayed.When sound wave is flowed to taper air outlet section, because the multiply air-flow mixes with certain helix angle, sound wave forms again interferes mutually and level of sound energy is further descended, and the air-flow of spiral motion when mixing the resistance eddy current be difficult to form or keep, thereby the gas flow resistance is descended.

This device makes the combination of former segmentation machinery become compound organic assembling, its structure advanced person, flow process can be by the decision of wing plate helical pitch, and helical pitch can be selected according to need, it is the several times of the outer length of silencing apparatus that the silencing apparatus that the application provides can make through-flow length, has improved acoustical absorptivity; Be equal under the noise reduction requirement condition, higher noise attentuation value and less windage are arranged, can in the frequency band range of broad, reduce exhaust sound greatly, effectively alleviated should the sound deadening capacity big little contradiction of resistance again: product with compact structure, firmly and less outward appearance volume arranged, thereby reduction materials consumption, improve working life, if can promote the use of, will produce good social benefit and economic benefit.

Claims

1. bull rotary wing type composite muffler, in circular and concentric, outer cylinder body (7,5), spiral fin (11), sound absorbing material compositions such as (6), it is characterized in that: circular cylinder body (7,5) two ends are connected with tubular suction port (2) and truncated cone rectification relief opening (10) by flange (4) respectively, one coaxial sound absorbing post (8) is arranged in the inner barrel (7) along its length, be furnished with spiral fin (11) between sound absorbing post and the inner barrel, all have some micropores on the wall of hollow sound absorbing post (8) and inner core (7), sound absorbing material (6) is loaded in the cavity between outer cylinder body and the inner barrel.

2. silencing apparatus according to claim 1 is characterized in that: the sound absorbing post two ends are connected with the reflector (3) and the deflector (9) of taper respectively.

3. silencing apparatus according to claim 1 is characterized in that: the fin of arranging along sound absorbing post (8) length direction in the inner barrel (7) (11) is a single-screw formula or how spiral, along the circumferential direction with the fin sub-multiple angle

Divide equally, N represents the fin number in the formula.

4. according to claim 1 or 3 described silencing apparatuss, it is characterized in that: spiral fin (11) but the discontinuous shape of short limb, the continuous shape of the long wing or sandwich-type fin.