CN108051076A - A kind of enclosure space panel-acoustic contribution degree recognition methods - Google Patents
A kind of enclosure space panel-acoustic contribution degree recognition methods Download PDFInfo
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Abstract
It the invention discloses a kind of enclosure space panel-acoustic contribution degree recognition methods, is set in portion in the enclosed space close to the holographic measurement face of inner surface, in grid type the distance between sound pressure sensor, neighbor mesh points is set to be less than half wavelength in measuring surface；Using the orthogonal spherical wave addition method, the transitive relation between measuring surface acoustic pressure and the source strength in orthogonal spherical wave source is established, calculates the source strength in orthogonal spherical wave source；According to the source strength in orthogonal spherical wave source, the transitive relation between enclosure space body structure surface normal direction vibration velocity and the source strength in orthogonal spherical wave source is established；Using the sound field principle of equal effects, enclosure space panel-acoustic contribution degree is calculated.The present invention is adaptable to the Enclosed sound field of arbitrary shape, and required measuring point quantity is few, is easy to implement.Since the different orders in the orthogonal spherical wave source of use have mutual orthogonality, the pathosis of transfer matrix is reduced, substantially increases computational accuracy.
Description
Technical field
The present invention relates to Noise Sources Identification method field, more particularly to a kind of enclosure space based on the superposition of orthogonal spherical wave
Panel-acoustic contribution degree recognition methods.
Technical background
By Complex Elastic closed cavity structure under dynamic excitation, vibration and the space sound field that is formed be engineering in practice most
It is representative one kind sound field, as automobile, ship and aircraft cabin in sound field.With people for life, working environment relax
Adaptive requirement is continuously improved, and the noise problem of enclosure space inside configuration is by people institute pay attention to day by day.Dynamic excitation energy transmission
To closed cavity structure, each panel vibration and then the irradiation structure noise into the operatic tunes are final to influence inside enclosure space, sound
The principal element of field characteristic is vibration and the acoustic characteristic for all plates for forming the operatic tunes.To forming each panel of enclosed construction
Acoustics Contribution Analysis is carried out, the panel that targetedly selection and the internal sound field of priority acccess control are affected, is that reduction is taken to make an uproar
Sound designs the key with Acoustic Optimization.
Existing enclosure space panel-acoustic contribution degree recognition methods mainly includes two classes：(1) it is based on finite element/border
First method modeling method.Nineteen ninety-five Zhang is based on acoustic boundary meta-model, it is proposed that closed cavity surrounding panels are to a certain in cavity
The contribution amount computational methods of site noise response.Mohanty in 2000 is empty using finite element and the numerical calculations of boundary element
Between sound field panel-acoustic contribution degree.Ding in 2002 is based on finite element numerical method and combines acoustics reciprocity measuring principle,
Propose the acoustics contribution degree algorithm of the internal portion's sound field of local panel vibration of the enclosed elastic thin plate operatic tunes.Wolff is carried within 2007
The enclosure space sound field panel-acoustic contribution degree algorithm based on Kirchhoff integral formulas is gone out.Han introduces " acoustics within 2009
Contribution and ", " acoustics contribution ratio " and the concept of " sound field is always contributed " carry, gone out a kind of to be suitable for multiple features site multiple response peak
The panel-acoustic contribution analysis method of value.Zhao Jing in 2010 proposes that passing through acoustics finite element method obtains structural vibration response, and
Recognition methods is contributed in this, as the panel-acoustic of acoustic boundary meta-model boundary condition.Li Suping is based on vehicle body knot within 2016
Structure-sound field FEM coupling model carries out panel-acoustic contribution analysis using Virtual.Lab business softwares.Such method
Computational accuracy is largely dependent upon the fine degree of model division unit and the degree of boundary condition simplification, simultaneously
It is huge there are calculation amount, the problem of computational efficiency is relatively low.(2) it is based on Nearfield acoustic holography.Hald is proposed and is based within 2006
The panel-acoustic contribution degree recognition methods of statistically optimal near-field acoustical holography used measurement, this method utilize two-sided array measurement enclosure space
The Near field acoustic information of each vibration panel in interior sound field, then reciprocity measurement is carried out by volume velocity sound source and obtains transmission letter
Number, so as to identify the acoustics contribution degree of arbitrary vibration panel in enclosure space structure.This method only need to be to interested panel
Carry out a Patch Near-field Acoustical Holography measurement, so that it may it obtains the position and the acoustics of sound field is contributed, without carrying out measurement of full field,
With preferable flexibility, but due to be still to carry out transmission function reciprocity measurement, there are workload it is huge the problem of.2013
Wu proposes the panel-acoustic contribution degree recognition methods of the near field acoustic holography based on Helmholtz least square methods.This method profit
With near field acoustic holography measurement technology, by being rebuild to the vibroacoustics response of complex vibration body structure surface, vibration plane is obtained
The surface sound intensity of plate, it is established that each contacting between the acoustical power stream of panel and the sound pressure level of specified site.But by its algorithm
Obtained panel-acoustic contribution degree is defined due to no positive and negative attribute, is respectively provided with certain limitation in practical applications.
2015, inside Nearfield acoustic holographies of the Xiao Yue based on equivalent source method, it is proposed that one kind can identify that complicated shape closing is empty
The computational methods of the panel-acoustic contribution degree of sound field in cavity configuration.This method rebuilds entire sound by one group of holography sound pressure measurement
Field information, acoustics contribution degree of each vibration panel of enclosed construction to any position in cavity is solved using the sound field principle of equal effects,
Have the characteristics that parameter is univocal, but this method needs to complete the acoustic measurement to the whole audience of entire enclosure space, it is desirable that cloth
The measuring point number put is more, adds measurement cost, exists simultaneously the problem of equivalent source position is chosen.
The content of the invention
Technical problem solved by the invention is the deficiency avoided present in the above-mentioned prior art, is provided a kind of based on orthogonal
Spherical wave superposition enclosure space panel-acoustic contribution degree recognition methods, simplify calculating process, improve wave source source strength arrange to
Measure computational accuracy.
The technical solution adopted by the present invention to solve the technical problems is as follows.A kind of enclosure space panel-acoustic contribution degree is known
Other method, feature is, comprises the following steps：
1) set in the enclosed space in portion close to the holographic measurement face of inner surface, acoustic pressure is set in grid type in measuring surface
The distance between sensor, neighbor mesh points is less than half wavelength, and the sound pressure sensor is located at measuring surface for measuring
Sound pressure level；
2) the orthogonal spherical wave addition method is utilized, the transmission established between measuring surface acoustic pressure and the source strength in orthogonal spherical wave source is closed
System calculates the source strength in orthogonal spherical wave source；It is as follows：
2.1 in the enclosed space portion arbitrarily choose and a little as origin establish spherical coordinate system, put using this as wave source position；
The positive direction of the x-axis, y-axis and z-axis of coordinate system meets the right-hand rule, and the origin of coordinate system elects enclosure space geometric center as；
Enclosure space structure plate according to orthogonal spherical wave principle of stacking, is vibrated inside steady sound field to be formed etc. by 2.2
The sound field to be generated by a series of orthogonal spherical wave source of different orders, varying strength is imitated, then under the coordinate system in sound field
Acoustic pressure at any position r=(r, θ, φ) is represented by：
In formula (1)：R is the distance between arbitrary point in orthogonal spherical wave source position and sound field, and θ is distance vector r
With the angle between z-axis positive direction,Angle between r and positive direction of the x-axis in the counterclockwise direction,For spheric harmonic function,For related Legendre functions；System
Relation between number j, m and n can be described as j=n2+n+m+1；N blocks rank for the orthogonal spherical wave source expansion item number of selection
Number；The orthogonal total exponent number J of spherical wave and the relation for blocking exponent number N are J=(N+1)2；jn(kr) it is first kind ball Bessel functions；The acoustic pressure generated for the orthogonal spherical wave of correspondence (n, m) rank；CjWith the orthogonal spherical surface of (n, m) rank
The source strength C of wave sourcenmIt is corresponding；
2.3 transitive relations established between measuring surface acoustic pressure and the source strength in orthogonal spherical wave source are as follows：
Ph=ΨphC (2)
In formula (2)：Ph=[p (rh,1),p(rh,2),…,p(rh,M)]TFor the acoustic pressure column vector of M measurement point on holographic facet,For the transmission in the orthogonal spherical wave source of each rank to each measurement point on holographic facet
Matrix, C=[C1,C2,…,CJ]TTo correspond to the column vector of the source strength in each rank orthogonal spherical wave source composition；
2.4 according to formula (2), and the measurement points M met on holographic facet is more than orthogonal spherical wave exponent number J, using singular value point
Solution technology uniquely determines the source strength in orthogonal spherical wave source：
C=(Ψph)+Ph (3)
In formula (3)：The generalized inverse of subscript "+" representing matrix；
3) according to the source strength in orthogonal spherical wave source, enclosure space body structure surface normal direction vibration velocity and orthogonal spherical wave source are established
Transitive relation between source strength：
Vs=ΨvsC (4)
In formula (4)：VsFor enclosure space body structure surface normal direction vibration velocity column vector, ΨvsFor the orthogonal spherical wave source of J ranks and vibration
Transfer matrix between body structure surface particle vibration velocity：
In formula (5)：ρ is Media density, and c is the sound propagation velocity in medium, and k=ω/c are sound wave wave number, and ω is angle
Frequency,For empty unit, S is enclosure space body structure surface node number；
4) association type (3) and (4), the transmission established between enclosure space body structure surface normal direction vibration velocity and measuring surface acoustic pressure are closed
System, can obtain closed cavity body structure surface normal direction vibration velocity column vector：
Vs=Ψvs(Ψph)+Ph (6)
5) using the sound field principle of equal effects, enclosure space panel-acoustic contribution degree is calculated；It is as follows：
5.1 according to the sound field principle of equal effects, and the acoustic pressure in enclosure space in sound field at any point may be considered due to group
Into the enclosure space all panel vibrations and at this caused by acoustic pressure be overlapped mutually generation, be expressed as：
In formula (7)：pfpFor the acoustic pressure in enclosure space internal acoustic field at arbitrary site r, pkFor by k-th of panel vibration and
Acoustic pressure component caused by the r, k=1,2 ..., K, K are the panel number for forming entire closing vibrational structure；
5.2, according to formula (1), the acoustic pressure in enclosure space internal acoustic field at arbitrary site r are expressed as：
pfp=ΨpC (8)
In formula (8)：Ψp=[ψp,1(rfp),ψp,2(rfp),…,ψp,J(rfp)] it is at the orthogonal spherical wave source of J ranks and site r
Transfer matrix between acoustic pressure；
Will as k-th of panel vibration acoustic pressure representation in components caused by the enclosed space in portion's sound field in the site
For：
pk=ΨpCk (9)
In formula (9)：CkFor the source strength column vector in the corresponding orthogonal spherical wave source of k-th of panel；
5.3 by all structural panels for vibrating the Enclosed sound field formed, according to formula (4), by the source in orthogonal spherical wave source
Strong column vector is expressed as：
In formula (10)：For the surface normal vibration velocity column vector of enclosure space structure, VskFor
The normal direction vibration velocity vector of k-th of panel；
5.4 physical significances contributed according to enclosure space panel-acoustic, are generated by k-th of panel vibration in certain site
Situation when acoustic pressure may be considered k-th panel individually vibration and the normal direction vibration velocity of other panels are zero, according to formula (10)
To the source strength column vector in the corresponding orthogonal spherical wave source of k-th of panel：
5.5 joints (9) and formula (11), are established as k-th of panel vibration and acoustic pressure caused by the site in enclosure
Component and the relation of k-th of panel surface normal direction vibration velocity are：
5.6 according to formula (5), by ΨvsIt is expressed as：
In formula (13)：PkFor all node numbers on k-th of panel of enclosure space structure, put in order as rk,1,,
rk,2,…,rk,Pk, and meetΨsvkIt is represented by：
5.7 association types (6) and formula (13), the relation for establishing k-th of panel surface normal direction vibration velocity and measuring surface acoustic pressure are：
5.8 association types (12) and formula (18), are established as k-th of panel vibration and sound caused by the site in enclosure
Pressure component and the relation of measuring surface acoustic pressure are：
5.9 association types (8) and formula (16) calculate acoustics contribution degree of k-th of the panel of enclosure space to internal acoustic field：
In formula (17)：Re expressions take real part, and subscript " * " represents complex conjugate.
Compared with the prior art, the present invention has the beneficial effect that：
1st, orthogonal expansion item number much less than discrete points in traditional finite element/boundary element method, avoids numerous
Trivial singular value processing and the nonuniqueness problem of solution, solution efficiency is high, does not have any limit to point position and reconstruction point position
System, is adaptable to the Enclosed sound field of arbitrary shape, and required measuring point quantity is few.
2nd, entire sound field and panel vibration information are rebuild by near-field holography measurement, avoids the sound of complicated sound and vibration system
Radiation and its calculating of coupling, simplify calculating process；
3rd, the different orders in the orthogonal spherical wave source used have mutual orthogonality, with this come the row of transfer matrix that construct
It is linear independence between vector, i.e. transfer matrix is sequency spectrum, reduces the pathosis of transfer matrix, is conducive to improve ripple
The source strength column vector calculation precision in source.
4th, it can be set, implemented simple and convenient at any point in portion in the enclosed space using orthogonal spherical wave source.
In short, the Enclosed sound field of arbitrary shape is adaptable to, and required measuring point quantity is few, is easy to implement.Due to using
Orthogonal spherical wave source different orders have mutual orthogonality, reduce the pathosis of transfer matrix, substantially increase calculating
Precision.
Description of the drawings
Fig. 1 is the spherical coordinate system schematic diagram that the present invention uses；
Fig. 2 is the enclosure space structural model schematic diagram of the embodiment of the present invention；
Fig. 3 is the results contrast of sound field observation point sound pressure level in the enclosure space of the embodiment of the present invention；
Fig. 4 (a) compares knot for acoustics contribution degree of each panel of enclosure space at crest frequency 46Hz of the embodiment of the present invention
Fruit；
Fig. 4 (b) compares knot for acoustics contribution degree of each panel of enclosure space at crest frequency 82Hz of the embodiment of the present invention
Fruit.
Specific embodiment
The present invention is made below in conjunction with drawings and examples into one into explanation.Referring to Fig. 1 to Fig. 4 (b), a kind of enclosure space
Panel-acoustic contribution degree recognition methods, is as follows：
A, set in the enclosed space in portion close to the holographic measurement face of inner surface, acoustic pressure is set in grid type in measuring surface
The distance between sensor, neighbor mesh points is less than half wavelength, and sound pressure sensor measurement is located at the sound in measuring surface
Pressure value；
B, using the orthogonal spherical wave addition method, the transmission established between measuring surface acoustic pressure and the source strength in orthogonal spherical wave source is closed
System calculates the source strength in orthogonal spherical wave source；
The step B is as follows：
B1, in the enclosed space portion arbitrarily choose and a little establish spherical coordinate system as origin, are put using this as wave source position.
The positive direction of the x-axis, y-axis and z-axis of coordinate system meets the right-hand rule, it is preferable that it is several that the coordinate origin elects enclosure space as
What center, as shown in Figure 1；
B2, according to orthogonal spherical wave principle of stacking, enclosure space structure plate is vibrated into inside steady sound field to be formed etc.
The sound field to be generated by a series of orthogonal spherical wave source of different orders, varying strength is imitated, then under the coordinate system in sound field
Acoustic pressure at any position r=(r, θ, φ) is represented by：
In formula (1)：R is the distance between arbitrary point in orthogonal spherical wave source position and sound field, and θ is distance vector r
With the angle between z-axis positive direction,Angle between r and positive direction of the x-axis in the counterclockwise direction,For spheric harmonic function,For related Legendre functions；System
Relation between number j, m and n can be described as j=n2+n+m+1；N blocks rank for the orthogonal spherical wave source expansion item number of selection
Number；The orthogonal total exponent number J of spherical wave and the relation for blocking exponent number N are J=(N+1)2；jn(kr) it is first kind ball Bessel functions；The acoustic pressure generated for the orthogonal spherical wave of correspondence (n, m) rank；CjWith the orthogonal spherical surface of (n, m) rank
The source strength C of wave sourcenmIt is corresponding；
B3, the transitive relation established between measuring surface acoustic pressure and the source strength in orthogonal spherical wave source are as follows：
Ph=ΨphC (2)
In formula (2)：Ph=[p (rh,1),p(rh,2),…,p(rh,M)]TFor the acoustic pressure column vector of M measurement point on holographic facet,For the transmission in the orthogonal spherical wave source of each rank to each measurement point on holographic facet
Matrix, C=[C1,C2,…,CJ]TTo correspond to the column vector of the source strength in each rank orthogonal spherical wave source composition；
B4, according to formula (2), the measurement points M met on holographic facet is more than orthogonal spherical wave exponent number J, using singular value point
Solution technology uniquely determines the source strength in orthogonal spherical wave source：
C=(Ψph)+Ph (3)
In formula (3)：The generalized inverse of subscript "+" representing matrix；
C, according to the source strength in orthogonal spherical wave source, enclosure space body structure surface normal direction vibration velocity and orthogonal spherical wave source are established
Transitive relation between source strength：
Vs=ΨvsC (4)
In formula (4)：VsFor enclosure space body structure surface normal direction vibration velocity column vector, ΨvsFor the orthogonal spherical wave source of J ranks and vibration
Transfer matrix between body structure surface particle vibration velocity
In formula (5)：ρ is Media density, and c is the sound propagation velocity in medium, and k=ω/c are sound wave wave number, and ω is angle
Frequency,For empty unit, S is enclosure space body structure surface node number；
D, association type (3) and (4), the transmission established between enclosure space body structure surface normal direction vibration velocity and measuring surface acoustic pressure are closed
System, can obtain closed cavity body structure surface normal direction vibration velocity column vector：
Vs=Ψvs(Ψph)+Ph (6)
E, using the sound field principle of equal effects, enclosure space panel-acoustic contribution degree is calculated.
The step E is as follows：
E1, according to the sound field principle of equal effects, the acoustic pressure in enclosure space in sound field at any point may be considered due to group
Into the enclosure space all panel vibrations and at this caused by acoustic pressure be overlapped mutually generation, be expressed as：
In formula (7)：pfpFor the acoustic pressure in enclosure space internal acoustic field at arbitrary site r, pkFor by k-th of panel vibration and
Acoustic pressure component caused by the r, k=1,2 ..., K, K are the panel number for forming entire closing vibrational structure；
E2, according to formula (1), the acoustic pressure in enclosure space internal acoustic field at arbitrary site r is expressed as：
pfp=ΨpC (8)
In formula (8)：Ψp=[ψp,1(rfp),ψp,2(rfp),…,ψp,J(rfp)] it is at the orthogonal spherical wave source of J ranks and site r
Transfer matrix between acoustic pressure.
Will as k-th of panel vibration acoustic pressure representation in components caused by the enclosed space in portion's sound field in the site
For：
pk=ΨpCk (9)
In formula (9)：Ck is the source strength column vector in the corresponding orthogonal spherical wave source of k-th of panel.
E3, for vibrating the Enclosed sound field formed by all structural panels, according to formula (4), by the source in orthogonal spherical wave source
Strong column vector is expressed as：
In formula (10)：For the surface normal vibration velocity column vector of enclosure space structure, VskFor
The normal direction vibration velocity vector of k-th of panel.
E4, the physical significance contributed according to enclosure space panel-acoustic, are generated by k-th of panel vibration in certain site
Situation when acoustic pressure may be considered k-th panel individually vibration and the normal direction vibration velocity of other panels are zero, according to formula (10)
To the source strength column vector in the corresponding orthogonal spherical wave source of k-th of panel：
E5, joint (9) and formula (11), are established as k-th of panel vibration and acoustic pressure caused by the site in enclosure
Component and the relation of k-th of panel surface normal direction vibration velocity are：
E6, according to formula (5), by ΨvsIt is expressed as：
In formula (13)：PkFor all node numbers on k-th of panel of enclosure space structure, put in order as rk,1,,
rk,2,…,rk,Pk, and meetΨsvkIt is represented by：
E7, association type (6) and formula (13), the relation for establishing k-th of panel surface normal direction vibration velocity and measuring surface acoustic pressure are：
E8, association type (12) and formula (18), are established as k-th of panel vibration and sound caused by the site in enclosure
Pressure component and the relation of measuring surface acoustic pressure are：
E9, association type (8) and formula (16) calculate acoustics contribution degree of k-th of the panel of enclosure space to internal acoustic field：
In formula (17)：Re expressions take real part, and subscript " * " represents complex conjugate.
The inspection of the method for the present invention：
In order to verify the enclosure space panel-acoustic contribution degree recognition methods based on the superposition of orthogonal spherical wave, similar vehicle is chosen
The irregular enclosure space internal acoustic field of end structure is analysis object, as shown in Figure 2.The enclosed construction is by front side board 1, back side panel
2nd, left plate 3, right plate 4, top plate 5, bottom plate 6 and inclined board 7 form.Each plate thickness of enclosure space structure is 2mm, material
Expect for sheet metal, density of material is 7.8 × 103kg/m3, elasticity modulus 210GPa, Poisson's ratio 0.3, system damping ratio
0.01, total is subject to the amplitude from bottom surface to be encouraged for 0.2N, frequency band 20~250Hz, and an excitation point position is
(0.388m,0.235m,0).Four angle points of pattern board 6 are fixed, in the enclosed space selected point (0.3m, 0.3m, 0.3m)
As acoustic pressure observation point.
It is in irregular shape due to the enclosure space structure, it can not be described with analytic expression, therefore using acoustic software
LMS Virtual.Lab carry out sound field calculating using acoustics FInite Element is coupled, by the acoustic pressure of each measuring point on obtained holographic facet
" input quantity " that value is rebuild as the internal NAH of progress, and the random noise that signal-to-noise ratio is 30dB is added in closer actual conditions.
Using the emulation acoustic pressure on the holographic facet of inside cavity as " measurement " data, sound field prediction and panel are carried out using the method for the present invention
Acoustics contribution degree calculates, and result of calculation is coupled acoustics FInite Element with use and is compared.
Fig. 3 is that sound field observation point sound in the method for the present invention and the enclosure space of coupling acoustics Finite element arithmetic is respectively adopted
The comparing result of pressure, it can be seen that the degree of agreement of the two is very good, illustrate the method for the present invention can accurately and effectively predict by
Sound field in the enclosure space that vibrational structure is formed.
Fig. 4 (a) and Fig. 4 (b) be respectively adopted the method for the present invention and couple acoustics Finite element arithmetic in 46Hz and
Each panel-acoustic contribution degree of enclosure space at the crest frequency of the two responses of 82Hz.As can be seen that in crest frequency 46Hz
At 82Hz, the acoustics contribution degree for calculating each vibration panel obtained using two methods all has higher uniformity, this
Illustrate that the method for the present invention can identify the acoustics contribution degree of each panel exactly.Meanwhile the acoustics tribute that the method for the present invention proposes
Degree of offering, which defines algorithm, can either provide the positive and negative attribute of acoustics contribution, and can be with the sound pressure level phase of the arbitrary site in internal acoustic field
Mutual correlation has preferable superiority, can be designed for Structural acoustic optimization and improvement provides more targeted foundation.
Claims (1)
1. a kind of enclosure space panel-acoustic contribution degree recognition methods, feature is, comprises the following steps：
1) set in the enclosed space in portion close to the holographic measurement face of inner surface, in grid type acoustic pressure is set to sense in measuring surface
The distance between device, neighbor mesh points is less than half wavelength, and the sound pressure sensor is located at the sound in measuring surface for measurement
Pressure value；
2) the orthogonal spherical wave addition method is utilized, establishes the transitive relation between measuring surface acoustic pressure and the source strength in orthogonal spherical wave source,
Calculate the source strength in orthogonal spherical wave source；It is as follows：
2.1 in the enclosed space portion arbitrarily choose and a little as origin establish spherical coordinate system, put using this as wave source position；Coordinate
The positive direction of the x-axis, y-axis and z-axis of system meets the right-hand rule, and the origin of coordinate system elects enclosure space geometric center as；
Enclosure space structure plate according to orthogonal spherical wave principle of stacking, is vibrated the inside steady sound field to be formed and is equivalent to by 2.2
The sound field generated by a series of orthogonal spherical wave source of different orders, varying strength, then it is arbitrary in sound field under the coordinate system
Acoustic pressure at position r=(r, θ, φ) is represented by：
In formula (1)：R is the distance between arbitrary point in orthogonal spherical wave source position and sound field, and θ is distance
Angle between vector r and z-axis positive direction,Angle between r and positive direction of the x-axis in the counterclockwise direction,For spheric harmonic function,For related Legendre functions；System
Relation between number j, m and n can be described as j=n2+n+m+1；N blocks rank for the orthogonal spherical wave source expansion item number of selection
Number；The orthogonal total exponent number J of spherical wave and the relation for blocking exponent number N are J=(N+1)2；jn(kr) it is first kind ball Bessel functions；The acoustic pressure generated for the orthogonal spherical wave of correspondence (n, m) rank；CjWith the orthogonal spherical surface of (n, m) rank
The source strength C of wave sourcenmIt is corresponding；
2.3 transitive relations established between measuring surface acoustic pressure and the source strength in orthogonal spherical wave source are as follows：
Ph=ΨphC (2)
In formula (2)：Ph=[p (rh,1),p(rh,2),…,p(rh,M)]TFor the acoustic pressure column vector of M measurement point on holographic facet,For the transmission in the orthogonal spherical wave source of each rank to each measurement point on holographic facet
Matrix, C=[C1,C2,…,CJ]TTo correspond to the column vector of the source strength in each rank orthogonal spherical wave source composition；
2.4 according to formula (2), and the measurement points M met on holographic facet is more than orthogonal spherical wave exponent number J, using singular value decomposition skill
Art uniquely determines the source strength in orthogonal spherical wave source：
C=(Ψph)+Ph (3)
In formula (3)：The generalized inverse of subscript "+" representing matrix；
3) according to the source strength in orthogonal spherical wave source, source strength of the enclosure space body structure surface normal direction vibration velocity with orthogonal spherical wave source is established
Between transitive relation：
Vs=ΨvsC (4)
In formula (4)：VsFor enclosure space body structure surface normal direction vibration velocity column vector, ΨvsFor the orthogonal spherical wave source of J ranks and vibrational structure
Transfer matrix between the particle vibration velocity of surface：
In formula (5)：ρ is Media density, and c is the sound propagation velocity in medium, and k=ω/c are sound wave wave number, and ω is angular frequency,For empty unit, S is enclosure space body structure surface node number；
4) transitive relation between enclosure space body structure surface normal direction vibration velocity and measuring surface acoustic pressure is established in association type (3) and (4),
It can obtain closed cavity body structure surface normal direction vibration velocity column vector：
Vs=Ψvs(Ψph)+Ph (6)
5) using the sound field principle of equal effects, enclosure space panel-acoustic contribution degree is calculated；It is as follows：
5.1 according to the sound field principle of equal effects, and the acoustic pressure in enclosure space in sound field at any point may be considered since composition should
All panel vibrations of enclosure space and acoustic pressure caused by this is overlapped mutually generation, be expressed as：
<mrow>
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<mi>p</mi>
<mrow>
<mi>f</mi>
<mi>p</mi>
</mrow>
</msub>
<mo>=</mo>
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<mo>&Sigma;</mo>
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In formula (7)：pfpFor the acoustic pressure in enclosure space internal acoustic field at arbitrary site r, pkFor by k-th of panel vibration and in r
Acoustic pressure component caused by place, k=1,2 ..., K, K are the panel number for forming entire closing vibrational structure；
5.2, according to formula (1), the acoustic pressure in enclosure space internal acoustic field at arbitrary site r are expressed as：
pfp=ΨpC (8)
In formula (8)：Ψp=[ψp,1(rfp),ψp,2(rfp),…,ψp,J(rfp)] for acoustic pressure at the orthogonal spherical wave source of J ranks and site r it
Between transfer matrix；
Will as k-th of panel vibration and acoustic pressure representation in components caused by the enclosed space in portion's sound field in the site is：
pk=ΨpCk (9)
In formula (9)：CkFor the source strength column vector in the corresponding orthogonal spherical wave source of k-th of panel；
5.3 by all structural panels for vibrating the Enclosed sound field formed, and according to formula (4), the source strength in orthogonal spherical wave source is arranged
Vector is expressed as：
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<mi>C</mi>
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<mo>(</mo>
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<mi>&Psi;</mi>
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<mi>v</mi>
<mi>s</mi>
</mrow>
</msub>
<mo>)</mo>
</mrow>
<mo>+</mo>
</msup>
<msup>
<mrow>
<mo>&lsqb;</mo>
<msubsup>
<mi>V</mi>
<mrow>
<mi>s</mi>
<mn>1</mn>
</mrow>
<mi>T</mi>
</msubsup>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<msubsup>
<mi>V</mi>
<mrow>
<mi>s</mi>
<mi>k</mi>
</mrow>
<mi>T</mi>
</msubsup>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<msubsup>
<mi>V</mi>
<mrow>
<mi>s</mi>
<mi>K</mi>
</mrow>
<mi>T</mi>
</msubsup>
<mo>&rsqb;</mo>
</mrow>
<mi>T</mi>
</msup>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>10</mn>
<mo>)</mo>
</mrow>
</mrow>
In formula (10)：For the surface normal vibration velocity column vector of enclosure space structure, VskFor kth
The normal direction vibration velocity vector of a panel；
5.4 physical significances contributed according to enclosure space panel-acoustic, the acoustic pressure generated by k-th of panel vibration in certain site
Situation when may be considered k-th panel individually vibration and the normal direction vibration velocity of other panels being zero, kth is obtained according to formula (10)
The source strength column vector in the corresponding orthogonal spherical wave source of a panel：
<mrow>
<msub>
<mi>C</mi>
<mi>k</mi>
</msub>
<mo>=</mo>
<msup>
<mrow>
<mo>(</mo>
<msub>
<mi>&Psi;</mi>
<mrow>
<mi>v</mi>
<mi>s</mi>
</mrow>
</msub>
<mo>)</mo>
</mrow>
<mo>+</mo>
</msup>
<msup>
<mrow>
<mo>&lsqb;</mo>
<mi>O</mi>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<msubsup>
<mi>V</mi>
<mrow>
<mi>s</mi>
<mi>k</mi>
</mrow>
<mi>T</mi>
</msubsup>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<mi>O</mi>
<mo>&rsqb;</mo>
</mrow>
<mi>T</mi>
</msup>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>11</mn>
<mo>)</mo>
</mrow>
</mrow>
5.5 joints (9) and formula (11), are established as k-th of panel vibration and acoustic pressure component caused by the site in enclosure
Relation with k-th of panel surface normal direction vibration velocity is：
<mrow>
<msub>
<mi>p</mi>
<mi>k</mi>
</msub>
<mo>=</mo>
<msub>
<mi>&Psi;</mi>
<mi>p</mi>
</msub>
<msup>
<mrow>
<mo>(</mo>
<msub>
<mi>&Psi;</mi>
<mrow>
<mi>v</mi>
<mi>s</mi>
</mrow>
</msub>
<mo>)</mo>
</mrow>
<mo>+</mo>
</msup>
<msup>
<mrow>
<mo>&lsqb;</mo>
<mi>O</mi>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<msubsup>
<mi>V</mi>
<mrow>
<mi>s</mi>
<mi>k</mi>
</mrow>
<mi>T</mi>
</msubsup>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<mi>O</mi>
<mo>&rsqb;</mo>
</mrow>
<mi>T</mi>
</msup>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>12</mn>
<mo>)</mo>
</mrow>
</mrow>
5.6 according to formula (5), by ΨvsIt is expressed as：
In formula (13)：PkFor all node numbers on k-th of panel of enclosure space structure, put in order forAnd meetΨsvkIt is represented by：
5.7 association types (6) and formula (13), the relation for establishing k-th of panel surface normal direction vibration velocity and measuring surface acoustic pressure are：
<mrow>
<msup>
<mrow>
<mo>&lsqb;</mo>
<mi>O</mi>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<msubsup>
<mi>V</mi>
<mrow>
<mi>s</mi>
<mi>k</mi>
</mrow>
<mi>T</mi>
</msubsup>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<mi>O</mi>
<mo>&rsqb;</mo>
</mrow>
<mi>T</mi>
</msup>
<mo>=</mo>
<msup>
<mrow>
<mo>&lsqb;</mo>
<mi>O</mi>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<msubsup>
<mi>&Psi;</mi>
<mrow>
<mi>s</mi>
<mi>v</mi>
<mi>k</mi>
</mrow>
<mi>T</mi>
</msubsup>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<mi>O</mi>
<mo>&rsqb;</mo>
</mrow>
<mi>T</mi>
</msup>
<msup>
<mrow>
<mo>(</mo>
<msub>
<mi>&Psi;</mi>
<mrow>
<mi>p</mi>
<mi>h</mi>
</mrow>
</msub>
<mo>)</mo>
</mrow>
<mo>+</mo>
</msup>
<msub>
<mi>P</mi>
<mi>h</mi>
</msub>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>15</mn>
<mo>)</mo>
</mrow>
</mrow>
5.8 association types (12) and formula (18) are established as k-th of panel vibration and acoustic pressure caused by the site in enclosure point
It measures and is with the relation of measuring surface acoustic pressure：
<mrow>
<msub>
<mi>p</mi>
<mi>k</mi>
</msub>
<mo>=</mo>
<msub>
<mi>&Psi;</mi>
<mi>p</mi>
</msub>
<msup>
<mrow>
<mo>(</mo>
<msub>
<mi>&Psi;</mi>
<mrow>
<mi>v</mi>
<mi>s</mi>
</mrow>
</msub>
<mo>)</mo>
</mrow>
<mo>+</mo>
</msup>
<msup>
<mrow>
<mo>&lsqb;</mo>
<mi>O</mi>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<msubsup>
<mi>&Psi;</mi>
<mrow>
<mi>s</mi>
<mi>v</mi>
<mi>k</mi>
</mrow>
<mi>T</mi>
</msubsup>
<mo>,</mo>
<mo>...</mo>
<mo>,</mo>
<mi>O</mi>
<mo>&rsqb;</mo>
</mrow>
<mi>T</mi>
</msup>
<msup>
<mrow>
<mo>(</mo>
<msub>
<mi>&Psi;</mi>
<mrow>
<mi>p</mi>
<mi>h</mi>
</mrow>
</msub>
<mo>)</mo>
</mrow>
<mo>+</mo>
</msup>
<msub>
<mi>P</mi>
<mi>h</mi>
</msub>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>16</mn>
<mo>)</mo>
</mrow>
</mrow>
5.9 association types (8) and formula (16) calculate acoustics contribution degree of k-th of the panel of enclosure space to internal acoustic field：
<mrow>
<msub>
<mi>D</mi>
<mi>k</mi>
</msub>
<mo>=</mo>
<mi>Re</mi>
<mrow>
<mo>(</mo>
<mfrac>
<mrow>
<msub>
<mi>p</mi>
<mi>k</mi>
</msub>
<mo>&CenterDot;</mo>
<msubsup>
<mi>p</mi>
<mrow>
<mi>f</mi>
<mi>p</mi>
</mrow>
<mo>*</mo>
</msubsup>
</mrow>
<mrow>
<mo>|</mo>
<msub>
<mi>p</mi>
<mrow>
<mi>f</mi>
<mi>p</mi>
</mrow>
</msub>
<msup>
<mo>|</mo>
<mn>2</mn>
</msup>
</mrow>
</mfrac>
<mo>)</mo>
</mrow>
<mo>-</mo>
<mo>-</mo>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mn>17</mn>
<mo>)</mo>
</mrow>
</mrow>
In formula (17)：Re expressions take real part, and subscript " * " represents complex conjugate.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109870669A (en) * | 2019-02-19 | 2019-06-11 | 重庆工业职业技术学院 | How soon a kind of two dimension claps mesh free compression Wave beam forming identification of sound source method |
| CN109932682A (en) * | 2019-02-19 | 2019-06-25 | 重庆工业职业技术学院 | How soon two dimension claps mesh free compression Wave beam forming identification of sound source method |
| CN110031796A (en) * | 2019-02-28 | 2019-07-19 | 重庆工业职业技术学院 | How soon a kind of three-dimensional claps mesh free compression Wave beam forming identification of sound source method |
| CN111157096A (en) * | 2020-01-06 | 2020-05-15 | 南昌工程学院 | Closed space panel acoustic contribution degree identification method based on local measurement |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103630232A (en) * | 2013-10-29 | 2014-03-12 | 南车青岛四方机车车辆股份有限公司 | Noise source identifying and testing method for high speed train |
| CN104765906A (en) * | 2015-03-03 | 2015-07-08 | 江苏大学 | Acoustic contribution analysis method of outer contour of tire |
| CN105844114A (en) * | 2016-04-28 | 2016-08-10 | 广西科技大学 | Non-conformal measurement near field acoustic holography sound field rebuilding method |
| CN105928614A (en) * | 2016-04-28 | 2016-09-07 | 广西科技大学 | Near-field acoustic holography fast algorithm based on complex ray wave superposition |
-
2017
- 2017-11-28 CN CN201711210467.9A patent/CN108051076A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103630232A (en) * | 2013-10-29 | 2014-03-12 | 南车青岛四方机车车辆股份有限公司 | Noise source identifying and testing method for high speed train |
| CN104765906A (en) * | 2015-03-03 | 2015-07-08 | 江苏大学 | Acoustic contribution analysis method of outer contour of tire |
| CN105844114A (en) * | 2016-04-28 | 2016-08-10 | 广西科技大学 | Non-conformal measurement near field acoustic holography sound field rebuilding method |
| CN105928614A (en) * | 2016-04-28 | 2016-09-07 | 广西科技大学 | Near-field acoustic holography fast algorithm based on complex ray wave superposition |
Non-Patent Citations (1)
| Title |
|---|
| 肖悦: "基于面板声学贡献度的封闭空腔结构内声场分析的若干关键问题研究", 《中国博士学位论文全文数据库工程科技辑Ⅱ辑》 * |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109870669A (en) * | 2019-02-19 | 2019-06-11 | 重庆工业职业技术学院 | How soon a kind of two dimension claps mesh free compression Wave beam forming identification of sound source method |
| CN109932682A (en) * | 2019-02-19 | 2019-06-25 | 重庆工业职业技术学院 | How soon two dimension claps mesh free compression Wave beam forming identification of sound source method |
| CN109932682B (en) * | 2019-02-19 | 2022-11-18 | 重庆工业职业技术学院 | Two-dimensional multi-snapshot non-grid compressed beam forming sound source identification method |
| CN110031796A (en) * | 2019-02-28 | 2019-07-19 | 重庆工业职业技术学院 | How soon a kind of three-dimensional claps mesh free compression Wave beam forming identification of sound source method |
| CN110031796B (en) * | 2019-02-28 | 2022-11-15 | 重庆工业职业技术学院 | Three-dimensional multi-snapshot non-grid compressed beam forming sound source identification method |
| CN111157096A (en) * | 2020-01-06 | 2020-05-15 | 南昌工程学院 | Closed space panel acoustic contribution degree identification method based on local measurement |
| CN111157096B (en) * | 2020-01-06 | 2022-01-28 | 南昌工程学院 | Closed space panel acoustic contribution degree identification method based on local measurement |
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