CN202756138U - Silencer capable of simultaneously eliminating noises of wide band and narrow band - Google Patents

Abstract

The utility model relates to the field of silencers and particularly provides a silencer capable of simultaneously eliminating noises of a wide band and a narrow band. The silencer comprises an annular air tube. An inner tube of the annular air tube is an airflow main tube. At least two resonant cavities are arranged in an outer tube of the annular air tube. The tube wall of the airflow main tube is provided with through holes. Each resonant cavity is communicated with the airflow main tube through at least one set of through holes. The outer tube wall of the annular air tube is composed of pipes with the same diameter or two or more different diameters through series connection. The resonant cavities are separated from each other through separating boards. Through adjustment of the width of the annular resonant cavities, the diameter and the number of the outer tubes and the aperture and the number of the through holes and through combination of the nonlinear least square method, better combination of the width, the diameter and the number of the resonant cavities and the aperture and the number of the through holes is optimized, and the effects of eliminating the noises of the wide band and the narrow band can be achieved. Moreover, the silencer is compact in structure and little in occupied space, and saves space on the premise of realizing silencing performance.

Description

A kind of silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise

Technical field

The utility model relates to the silencing apparatus field, relates in particular to a kind of silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise.

Background technique

Automobile occupies very large share as the important product in industrial products field.Yet automobile advances the physical and mental health that the heat-extraction system noise has a strong impact on people, therefore, must control the noise that air inlet system and exhaust system produce.And one of the rational silencing apparatus of mounting structure effective measures that are control inlet and exhaust system noise, present big-and-middle-sized diesel engine has been realized supercharging substantially, and increasing petrol engine has been realized supercharging.Supercharged engine has brought new problem to noise and vibration and the road traffic noise of automobile.Can produce obvious howling during turbocharger operation, frequency range is approximately 1.5～4KHz, and frequency range is wider, needs this noise of establishment.At present, the measure that solves the engine aspirating system noise on the automobile mainly comprises arranges expansion silencing apparatus, Helmholtz silencing apparatus and some 1/4 wavelength pipes, but because they can only eliminate the noise of single frequency band separately, can't eliminate wideband noise, and be subjected to the restriction of mounting point, can not satisfying in the situation of acoustical behavior, accomplish compact structure.After considering the multinomial requirements such as space and environment, be necessary to realize wide band and narrow-band noise elimination with the silencer of a compactness.

The at present design of silencing apparatus mainly also is based on experience, lacks complete design theory, and the design cycle is long.The sound field that existing numerical computation method is found the solution silencing apparatus inside often can not in time reflect the structural parameter variation efficiently on the impact of transmission loss, and from the processing that anaphase is prepared in the modeling in early stage, often lasts longer.Aspect theoretical algorithm, also do not propose to be used for the simple to operate of engineering, carry out efficient algorithm.Therefore, be necessary to propose a kind of suitable engineering, be used for calculating the algorithm of the transmission loss of multi-cavity perforated muffler.This patent proposes a kind of improvement algorithm based on Plane wave theory and transfer matrix method, and it can calculate the transmission loss in a plurality of chambeies more accurately, simultaneously again in conjunction with using nonlinear least square method to seek optimal solution.Flexibly, convenient, efficiently, can greatly improve the design efficiency of this type of silencing apparatus.

The model utility content

The problem that exists for solving prior art, the utility model provides a kind of compact structure, can eliminate simultaneously wide band and narrow frequency band noise, silencing apparatus simple in structure.

The silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise described in the utility model, it comprises a ring

Shape tracheae, the inner tube of described annular gas pipe are the air-flow supervisor, and at least two resonant cavities are set in the outer tube of described annular gas pipe, and described air-flow supervisor's tube wall arranges perforation, and each resonant cavity is communicated with described air-flow supervisor by at least one group of described perforation; The outer tube wall of described annular gas pipe is in series by same diameter or by two kinds and above different-diameter pipeline, in order to increase the width of noise elimination frequency band, realizes that wide band and narrow-band are mixed to eliminate the noise; Use baffle for separating between the described resonant cavity; Can realize eliminating wide band and narrow frequency band noise by width, diameter and the number of adjustment resonant cavity and aperture and the number of perforation.

Aperture in the described perforation on the same group is identical.

Described silencing apparatus is made by hexamethylene terephthalamide (PA6T/66).

Utilization is calculated the transmission loss of resonant cavity based on the improvement algorithm of Plane wave theory and transfer matrix method, and seeks resonant cavity width, diameter, number and the aperture of perforation and the more excellent combination of number in conjunction with nonlinear least square method.

The width of described resonant cavity is disposed in order from the annular gas pipe end to end is descending or ascending.

Penetration depth is determined by the wall thickness of described annular gas pipe, therefore can change penetration depth by adjusting wall thickness.

Preferably, the air-flow predominant tube diameter 41.6mm of described silencing apparatus, air-flow supervisor wall thickness 2.8mm, resonant cavity is five, the resonant cavity width is respectively: 10.4mm, 13.8mm, 18.6mm, 15.2mm, 15.2mm, the resonant cavity diameter is respectively: 69mm, 69mm, 69mm, 75mm, 75mm, the identical perforation of aperture, hole count of five corresponding five groups of circumferential arrangement of resonant cavity, the perforation hole count that each resonant cavity is corresponding is respectively: 28,28,28,20,20, the aperture is respectively: 3mm, 3mm, 3mm, 2.5mm, 2.5mm.

Preferably, the air-flow predominant tube diameter 41.6mm of described silencing apparatus, air-flow supervisor wall thickness 2.8mm, resonant cavity is five, the resonant cavity width is respectively: 10.5mm, 13.9mm, 17.2mm, 9.6mm, 9.6mm, the resonant cavity diameter is respectively: 69mm, 69mm, 69mm, 75mm, 75mm, the identical perforation of aperture, hole count of five corresponding five groups of circumferential arrangement of resonant cavity, the perforation hole count that each resonant cavity is corresponding is respectively: 28,28,28,20,20, the aperture is respectively: 3mm, 3mm, 2.9mm, 2mm, 2mm.

Preferably, the air-flow predominant tube diameter 41.6mm of described silencing apparatus, air-flow supervisor wall thickness 2.8mm, resonant cavity is five, the resonant cavity width is respectively: 11.6mm, 13.6mm, 17.1mm, 9.6mm, 9.6mm, the resonant cavity diameter is respectively: 69mm, 69mm, 69mm, 75mm, 75mm, the identical perforation of aperture, hole count of five corresponding five groups of circumferential arrangement of resonant cavity, the perforation hole count that each resonant cavity is corresponding is respectively: 30,28,36,20,20, the aperture is respectively: 3mm, 2.6mm, 2.8mm, 2mm, 2mm.

The silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise described in the utility model, its beneficial effect is:

(1) main structure of silencing apparatus is the tracheae of an annular, inner tube is the air-flow supervisor, resonant cavity is set in appearance, by width, outer tube diameter and the number of adjustment ring resonance and aperture and the number of perforation, improvement algorithm based on Plane wave theory and transfer matrix method, calculate the transmission loss of resonant cavity, and in conjunction with the aperture of nonlinear least square method optimization resonant cavity width, diameter, number and perforation and the more excellent combination of number, can realize eliminating the effect of broadband and narrow band noise.The outer tube wall of annular gas pipe is in series by same diameter or two kinds and above different-diameter pipeline, in order to increase the width of noise elimination frequency band, realizes that wide band and narrow-band are mixed to eliminate the noise.

(2), a plurality of Helmholtz silencing apparatus profile series connection and integrated, compact structure occupies little space, and has saved the space satisfying under the prerequisite of acoustic attenuation performance.

Description of drawings

The picture that this description of drawings provides is used for assisting the further understanding to model utility, consists of the application's a part, does not consist of to improper restriction of the present utility model, in the accompanying drawings:

Accompanying drawing 1 can be eliminated the internal structure schematic representation of the silencing apparatus of wide band and narrow frequency band noise simultaneously for the utility model.

Accompanying drawing 2 can be eliminated the external structure schematic representation of the silencing apparatus of wide band and narrow frequency band noise simultaneously for the utility model.

Accompanying drawing 3 is that the utility model is without the transmission loss curve of parameter optimization.

Accompanying drawing 4 is the utility model gas handling system noise reduction aim curve.

Accompanying drawing 5 can be eliminated transmission loss curve and the aim curve after embodiment's 1 parameter optimization of silencing apparatus of wide band and narrow frequency band noise simultaneously for the utility model.

Accompanying drawing 6 can be eliminated transmission loss curve and the aim curve after embodiment's 2 parameter optimizations of silencing apparatus of wide band and narrow frequency band noise simultaneously for the utility model.

Accompanying drawing 7 can be eliminated transmission loss curve and the aim curve after embodiment's 3 parameter optimizations of silencing apparatus of wide band and narrow frequency band noise simultaneously for the utility model.

Accompanying drawing 8 can be eliminated the algorithm flow chart of the silencing apparatus of wide band and narrow frequency band noise simultaneously for the utility model.

Embodiment

The below will describe the present invention in detail with specific embodiment, be used for explaining the utility model in this illustrative examples of the present utility model and explanation, but not as to restriction of the present utility model.

Shown in accompanying drawing 1,2, the silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise of the present invention, comprise an annular gas pipe, the inner tube 4 of described annular gas pipe is the air-flow supervisor, at least two ring resonances of outer tube 2 interior settings 3 of described annular gas pipe have perforation 1 on described air-flow supervisor's 4 the tube wall, and each ring resonance is communicated with described air-flow supervisor 4 by at least one group of described perforation, if each resonant cavity correspondence is organized perforation more, then perforation circumferentially is evenly arranged in around the tube wall.Separate with toroidal membrane 5 between the ring resonance 3.

The outer tube wall of described annular gas pipe is in series by same diameter or two kinds and above different-diameter pipeline, in order to increase the width of noise elimination frequency band, realizes that wide band and narrow-band are mixed to eliminate the noise.Described silencing apparatus is made by hexamethylene terephthalamide (PA6T/66).

For the ease of making, the width of resonant cavity is disposed in order from the annular gas pipe end to end is descending or ascending.Penetration depth is determined by the wall thickness of described annular gas pipe, therefore can change penetration depth by the adjustment wall thickness and reach different soundproof effects.

Described silencing apparatus can realize eliminating wide band and narrow frequency band noise by width, diameter and the number of adjustment ring resonance and aperture and the number of perforation.

The improvement algorithm that the present invention is based on Plane wave theory and transfer matrix method can calculate the transmission loss in a plurality of chambeies more accurately, use nonlinear least square method accurately to seek the optimal solution of Different structural parameters combination, these computational methods can be verified the transmission loss of existing structure, by the real time altering parameter, can carry out structure different designs parameter to the sensitivity analysis of transmission loss impact, make things convenient for design modifying, arrowband for the different frequency section, the acoustic characteristics energy of broadband or arrowband and broadband combination, these computational methods can be fast, accurately seek the optimal solution of Different structural parameters combination.

Based on the improvement algorithm of Plane wave theory and transfer matrix method, the transmission loss of calculating resonant cavity is as follows:

At perforated tube portion, the acoustic pressure in the perforated pipe and particle vibration velocity are respectively and are made as p ₁And u ₁, acoustic pressure and particle vibration velocity in the resonant cavity are respectively p ₂And u ₂, under the simple harmonic wave hypothesis, be respectively with the interior ACOUSTIC WAVE EQUATION of resonant cavity in the perforated pipe:

$\frac{{\&PartialD;}^2{p}_1}{{\&PartialD;x}^2}+\frac{M_1}{M_1-1}(j2{\mathrm{<figure-callout\; id="0"\; label="k"\; filenames="HDA00002001046100031.png,HDA00002001046100061.png"\; state="\{\{state\}\}">k</figure-callout>}}_0+\frac{4}{\mathrm{d\&xi;}})\frac{{\&PartialD;p}_1}{\&PartialD;x}+\frac{1}{{M_1}^2-1}(\frac{j4{\mathrm{<figure-callout\; id="0"\; label="k"\; filenames="HDA00002001046100031.png,HDA00002001046100061.png"\; state="\{\{state\}\}">k</figure-callout>}}_0}{\mathrm{d\&xi;}}-{\mathrm{<figure-callout\; id="0"\; label="k"\; filenames="HDA00002001046100031.png,HDA00002001046100061.png"\; state="\{\{state\}\}">k</figure-callout>}}_0^2)p_1-\frac{M_1}{M_1^2-1}\frac{4}{\mathrm{d\&xi;}}\frac{{\&PartialD;p}_2}{\&PartialD;x}-\frac{1}{M_1^2-1}\frac{j4{\mathrm{<figure-callout\; id="0"\; label="k"\; filenames="HDA00002001046100031.png,HDA00002001046100061.png"\; state="\{\{state\}\}">k</figure-callout>}}_0}{\mathrm{d\&xi;}}{p}_2=0---\left(1\right)$

$\frac{{\&PartialD;}^2{p}_2}{{\&PartialD;x}^2}+\frac{M_2}{M_2-1}(j2{\mathrm{<figure-callout\; id="0"\; label="k"\; filenames="HDA00002001046100031.png,HDA00002001046100061.png"\; state="\{\{state\}\}">k</figure-callout>}}_0+\frac{4d}{(D^2-d^2)\mathrm{\&xi;}})\frac{{\&PartialD;p}_2}{\&PartialD;x}+\frac{1}{{M_2}^2-1}(\frac{j4d{k}_0}{(D^2-d^2)\mathrm{\&xi;}}-{\mathrm{<figure-callout\; id="0"\; label="k"\; filenames="HDA00002001046100031.png,HDA00002001046100061.png"\; state="\{\{state\}\}">k</figure-callout>}}_0^2)p_2-\frac{M_2}{M_2^2-1}\frac{4d}{(D^2-d^2)\mathrm{\&xi;}}\frac{{\&PartialD;p}_1}{\&PartialD;x}-\frac{1}{M_2^2-1}\frac{j4d{k}_0}{(D^2-d^2)\mathrm{\&xi;}}{p}_1=0---\left(2\right)$

In the formula: ρ ₀c ₀ξ is the perforation acoustic impedance of perforated pipe, utilizes the perforation acoustic impedance to set up in the perforated pipe and the relation of the acoustic pressure in the resonant cavity ₀c ₀ξ=(p ₁-p ₂)/u, u are the particle vibration velocity in the perforated pipe, k ₀Be wave number, M ₁, M ₂For in the perforated pipe with resonant cavity in Mach number.

Formula (1) and (2) are obtained the transfer matrix at perforated pipe two ends by computing and abbreviation:

$\left\{\begin{array}{c}{p}_1\left(0\right)\\ {\mathrm{\&rho;}}_0{c}_0{u}_2\left(0\right)\end{array}\right\}=\left[T\right]\left\{\begin{array}{c}{p}_1\left(l_p\right)\\ {\mathrm{\&rho;}}_0{c}_0{u}_2\left(l_p\right)\end{array}\right\}---\left(3\right)$

By formula (3) and then try to achieve the transmission loss of single resonant cavity

$\mathrm{TL}=20{\log }_{10}\left(\frac{1}{2}\right|T_{11}+T_{12}+T_{21}+T_{22}\left|\right)---\left(4\right)$

If this silencing apparatus is many structure of resonant cavity, then total transfer matrix is:

$\left[T\right]=\left[T_N\right]...\left[T_i\right]...\left[T_1\right]=\left[\begin{array}{cc}{T}_{N,11}& T_{N,12}\\ T_{N,21}& T_{N,22}\end{array}\right]...\left[\begin{array}{cc}{T}_{i,11}& T_{i,12}\\ T_{i,21}& T_{i,22}\end{array}\right]...\left[\begin{array}{cc}{T}_{\mathrm{1,11}}& T_{\mathrm{1,12}}\\ T_{\mathrm{1,21}}& T_{\mathrm{1,22}}\end{array}\right]---\left(5\right)$

Transmission loss by formula (4) and (5) and then many structure of resonant cavity is:

$\mathrm{TL}=20{\log }_{10}\left(\frac{1}{2}\right|T_{N,11}+T_{N,12}+T_{N,21}+T_{N,22}\left|\right)+...+20{\log }_{10}\left(\frac{1}{2}\right|T_{i,11}+T_{i,12}+T_{i,21}+T_{i,22}\left|\right)$ (6)

$+...+20{\log }_{10}\left(\frac{1}{2}\right|T_{\mathrm{1,11}}+T_{\mathrm{1,12}}+T_{\mathrm{1,21}}+T_{\mathrm{1,22}}\left|\right)$

It is as follows to utilize nonlinear least square method to seek the basic ideas of optimal solution:

$\underset{x}{\min }\mathrm{sum}\left\{\mathrm{func}\right\{{(f,X)}^2\}---\left(7\right)$

func(f,X)＝objection(f)-Transimission_Loss(f,X);

In the formula, objection (f) is aim curve, and wherein f is frequency; The curve of Transimission_Loss (f, X) for optimizing, f is frequency, X is superior vector.

Based on the flow chart of this algorithm as shown in Figure 8.

Optimized project and result below are provided, arrange:

The structural parameter of a, initial wideband noise silencing apparatus: resonant cavity diameter d out=69mm, air-flow predominant tube diameter din=41.6mm, air-flow supervisor wall thickness tw=2.8mm, resonant cavity is counted num=5, remaining variables data such as table 1:

Table 1 wide band initializaing variable parameter value table

B, initial narrow frequency band noise acoustic wave filter structure parameter (invariant): resonant cavity diameter d out=75mm, air-flow predominant tube diameter din=41.6mm, air-flow supervisor wall thickness tw=2.8mm, resonant cavity is counted num=2, remaining variables such as table 2:

Table 2 narrow-band initializaing variable parameter value table

Use above-mentioned improvement algorithm to calculate transmission loss:

Transmission loss curve as calculated is such as accompanying drawing 3, be written into gas handling system noise reduction aim curve such as accompanying drawing 4, as can be seen from Figure 4, the transmission loss curve that is not optimized can not satisfy this silencing apparatus and require silencing apparatus can eliminate the acoustics requirement of narrow-band and wideband noise.

In order to realize eliminating simultaneously wide band and narrow frequency band noise, each parameter is optimized, optimized variable is set, determine the optimization range of variable:

At first, select the number of optimized variable, in order to take into account engineering demand, three kinds of schemes be set:

(1) resonant cavity is wide variable, and piercing aperture and hole count are immutable.

(2) resonant cavity is wide, and piercing aperture is variable, and hole count is immutable.

(3) resonant cavity is wide, and piercing aperture, hole count are all variable.

Embodiment 1

(1) the kind scheme of choosing is optimized, and namely resonant cavity is wide variable, and piercing aperture and hole count are immutable.

The wide band dimension constraint value table of table 3 for setting:

Table 3 wide band dimension constraint value table

Table 4 is narrow-band dimension constraint table:

Table 4 narrow-band dimension constraint value table

After optimizing, obtain optimum results such as the table 5 of parameter:

Table 5 optimum results

Transmission loss curve after the optimization and aim curve such as accompanying drawing 5, as can be seen from the figure, with the aim curve contrast, Optimal Curve satisfies aim curve substantially, and the silencing apparatus after therefore optimizing can satisfy eliminates wide band and narrow frequency band noise simultaneously.

So, present embodiment after optimizing the narrow-band eliminated and the acoustic wave filter structure parameter of wideband noise be:

Several 5 of air-flow predominant tube diameter 41.6mm, air-flow supervisor wall thickness 2.8mm, resonant cavity, its diameter is respectively: 69mm, 69mm, 69mm, 75mm, 75mm, corresponding resonant cavity width is respectively: 10.4mm, 13.8mm, 18.6mm, 15.2mm, 15.2mm, the identical perforation of aperture, hole count of the corresponding five groups of circumferential arrangement of each resonant cavity, five perforation hole counts corresponding to resonant cavity are respectively: 28,28,28,20,20, corresponding piercing aperture is respectively: 3mm, 3mm, 3mm, 2.5mm, 2.5mm.

Embodiment 2

(2) the kind scheme of choosing is optimized, and resonant cavity is wide, and piercing aperture is variable, and hole count is immutable.

The wide band dimension constraint value table of table 6 for setting:

Table 6 wide band dimension constraint value table

Table 7 is narrow-band dimension constraint table:

Table 7 narrow-band dimension constraint value table

After optimizing, obtain optimum results such as the table 8 of parameter:

Table 8 optimum results

Transmission loss curve after the optimization and aim curve such as accompanying drawing 6, as can be seen from the figure, with the aim curve contrast, Optimal Curve satisfies aim curve substantially, and the silencing apparatus after therefore optimizing can satisfy eliminates wide band and narrow frequency band noise simultaneously.

So, present embodiment after optimizing the narrow-band eliminated and the acoustic wave filter structure parameter of wideband noise be:

Several 5 of air-flow predominant tube diameter 41.6mm, air-flow supervisor wall thickness 2.8mm, resonant cavity, its diameter is respectively: 69mm, 69mm, 69mm, 75mm, 75mm, corresponding resonant cavity width is respectively: 10.5mm, 13.9mm, 17.2mm, 9.6mm, 9.6mm, the identical perforation of aperture, hole count of the corresponding five groups of circumferential arrangement of each resonant cavity, five perforation hole counts corresponding to resonant cavity are respectively: 28,28,28,20,20, the aperture is respectively: 3mm, 3mm, 2.9mm, 2mm, 2mm.

Embodiment 3

(3) the kind scheme of choosing is optimized, and resonant cavity is wide, and piercing aperture is variable, and hole count is immutable.

The wide band dimension constraint value table of table 9 for setting:

Table 9 wide band dimension constraint value table

Table 10 is narrow-band dimension constraint table:

Table 10 narrow-band dimension constraint value table

After optimizing, obtain optimum results such as the table 11 of parameter:

Table 11 optimum results

Transmission loss curve after the optimization and aim curve such as accompanying drawing 7, as can be seen from the figure, with the aim curve contrast, Optimal Curve satisfies aim curve substantially, and the silencing apparatus after therefore optimizing can satisfy eliminates wide band and narrow frequency band noise simultaneously.

So, present embodiment after optimizing the narrow-band eliminated and the acoustic wave filter structure parameter of wideband noise be:

Several 5 of air-flow predominant tube diameter 41.6mm, air-flow supervisor wall thickness 2.8mm, resonant cavity, its diameter is respectively: 69mm, 69mm, 69mm, 75mm, 75mm, corresponding resonant cavity width is respectively: 11.6mm, 13.6mm, 17.1mm, 9.6mm, 9.6mm, the corresponding five groups of apertures of each resonant cavity, the perforation that hole count is identical, the perforation hole count of the circumferential arrangement that five resonant cavities are corresponding is respectively: 30,28,36,20,20, the aperture is respectively: 3mm, 2.6mm, 2.8mm, 2mm, 2mm.

Embodiment 4:

The setting of above optimized variable is not limited only to above-mentioned numerical value, can also can select other scheme according to actual conditions parameters numerical value, uses this method to be optimized.

More than technological scheme that the utility model embodiment is provided be described in detail, used specific case herein the utility model embodiment's principle and mode of execution are set forth, above embodiment's explanation is only applicable to help to understand the utility model embodiment's principle; Simultaneously, for one of ordinary skill in the art, according to the embodiment of the invention, all will change on embodiment and application area, in sum, this description should not be construed as restriction of the present utility model.

Claims (7)

1. the silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise is characterized in that:

Comprise an annular gas pipe, the inner tube of described annular gas pipe is the air-flow supervisor, outside the described annular gas pipe

At least two resonant cavities are set in the pipe, and described air-flow supervisor's tube wall arranges perforation, and each resonant cavity is communicated with described air-flow supervisor by at least one group of described perforation;

The outer tube wall of described annular gas pipe is by same diameter or by the series connection of two kinds and above different-diameter pipeline

Become, in order to increase the width of noise elimination frequency band, realize wide band and narrow-band mixing noise elimination;

Use baffle for separating between the described resonant cavity; Width, diameter and number by adjusting resonant cavity and

Aperture and the number of perforation can realize eliminating wide band and narrow frequency band noise.

2. can eliminate simultaneously as claimed in claim 1 the silencing apparatus of wide band and narrow frequency band noise, it is characterized in that: the aperture in the described perforation on the same group is identical.

3. the silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise as claimed in claim 1, it is characterized in that: the width of described resonant cavity is disposed in order from the annular gas pipe end to end is descending or ascending.

4. the silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise as claimed in claim 1 is characterized in that: can change penetration depth by the wall thickness of adjusting the air-flow supervisor.

5. the silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise as claimed in claim 1, it is characterized in that: the air-flow predominant tube diameter 41.6mm of described silencing apparatus, air-flow supervisor wall thickness 2.8mm, resonant cavity is five, the resonant cavity width is respectively: 10.4mm, 13.8 mm, 18.6 mm, 15.2 mm, 15.2 mm, the resonant cavity diameter is respectively: 69 mm, 69 mm, 69 mm, 75 mm, 75 mm, the aperture of five corresponding five groups of circumferential arrangement of resonant cavity, the perforation that hole count is identical, the perforation hole count that each resonant cavity is corresponding is respectively: 28,28,28,20,20, the aperture is respectively: 3 mm, 3 mm, 3 mm, 2.5 mm, 2.5 mm.

6. the silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise as claimed in claim 1, it is characterized in that: the air-flow predominant tube diameter 41.6mm of described silencing apparatus, air-flow supervisor wall thickness 2.8mm, resonant cavity is five, the resonant cavity width is respectively: 10.5 mm, 13.9 mm, 17.2 mm, 9.6 mm, 9.6 mm, the resonant cavity diameter is respectively: 69 mm, 69 mm, 69 mm, 75 mm, 75 mm, the aperture of five corresponding five groups of circumferential arrangement of resonant cavity, the perforation that hole count is identical, the perforation hole count that each resonant cavity is corresponding is respectively: 28,28,28,20,20, the aperture is respectively: 3 mm, 3 mm, 2.9 mm, 2 mm, 2 mm.

7. the silencing apparatus that can eliminate simultaneously wide band and narrow frequency band noise as claimed in claim 1, it is characterized in that: the air-flow predominant tube diameter 41.6mm of described silencing apparatus, air-flow supervisor wall thickness 2.8mm, resonant cavity is five, the resonant cavity width is respectively: 11.6 mm, 13.6 mm, 17.1 mm, 9.6 mm, 9.6 mm, the resonant cavity diameter is respectively: 69 mm, 69 mm, 69 mm, 75 mm, 75 mm, the aperture of five corresponding five groups of circumferential arrangement of resonant cavity, the perforation that hole count is identical, the perforation hole count that each resonant cavity is corresponding is respectively: 30,28,36,20,20, the aperture is respectively: 3 mm, 2.6 mm, 2.8 mm, 2 mm, 2 mm.

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