CN102494754B - Rapid identification method of noise source contributions in car based on order dispersion - Google Patents

Abstract

The invention discloses a rapid identification method of noise source contributions in a car based on order dispersion, and the method comprises the following steps of: step 1, collecting full-load acceleration noise vibration; step 2, carrying out whole-car sound transmission loss test; step 3, carrying out whole car structure-acoustic transfer function test; step 4, rapidly indentifying the noise source contributions in the car; and step 5, carrying out simplification and overlapping based on order analysis. According to the invention, a main noise source and a main transmission path in the car can be rapidly identified and a reliable solution is provided for solving the problem of the noise in the car; and the detection period is shortened and the cost for researching the car NVH (Noise Vibration and Harshness) is reduced.

Description

A kind of based on the discrete internal car noise source contribution amount method for quickly identifying of order

Technical field

The present invention relates to the evaluation method of automobile vibration noise, be specifically related to a kind of based on the discrete internal car noise source contribution amount method for quickly identifying of order.

Background technology

The NVH(noise and vibration of automobile) become one of most important index in automobile brand.The attraction core of numerous auto vendors using excellent NVH performance as its product, the automobile of excellent NVH performance, is representing brand's equity and meaning.How analyzing faster NVH problem, find out and have weakness, form through engineering approaches solution, is the key element that promotes NVH performance.In to noise and vibration contribution quantitative analysis, the identification to source and transport function, classic method adopts the discrete and integrated approach based on third-octave, and in the identification of construct noise, there is frequency out of true in this kind of method, the problem that order noise cannot extract.Therefore, need to separately seek approach.

Summary of the invention

The object of this invention is to provide a kind of based on the discrete internal car noise source contribution amount method for quickly identifying of order, the method, when research car load internal car noise driving source and bang path thereof, can correctly be identified each driving source and bang path thereof the size to noise and vibration contribution amount fast.

Of the present invention a kind of based on the discrete internal car noise source contribution amount method for quickly identifying of order, comprise the steps:

The first step, the collection of full load acceleration noise vibration;

(1) sensor is arranged in to driver and each occupant's ears place, nacelle six surfaces, portings, the main quilt that suspends moved end and exhaust lifting lug main quilt moved end in car; The microphone (microphone) that makes to be arranged in car is 10cm ± 1cm with the distance of backrest, and in same level height; Make to be arranged in the positional distance Engine Surface 10cm ± 1cm of the microphone in nacelle; Make to be arranged in the microphone at air intake opening place and the distance of air intake opening is 15cm, and microphone is over against air intake opening; Making to be arranged in the microphone of exhausr port and the distance of exhausr port is 50cm, and the axis of reference of microphone should be parallel to the ground, and and by the plane of exhausr port airflow direction and vertical ground at 45 ° ± angle of 10 °;

(2) carry out the collection of second gear full throttle acceleration noise, at least carry out above collection 3 times, extract full band frequency range noise Value Data;

Second step, car load sound transmission loss (TL) test;

(1) by microphone arrangement driver and each occupant's ears place, six surfaces of nacelle, porting in car; Making to be arranged in microphone in car and the distance of backrest is 10cm ± 1cm, and in same level height; Make to be arranged in the positional distance Engine Surface 10cm ± 1cm of the microphone in nacelle; Make to be arranged in the microphone at air intake opening place and the distance of air intake opening is 15cm, and microphone is over against air intake opening; Making to be arranged in the microphone of exhausr port and the distance of exhausr port is 50cm, and the axis of reference of microphone should be parallel to the ground, and and by the plane of exhausr port airflow direction and vertical ground at 45 ° ± angle of 10 °;

(2) volume sound source (can send the noise device of different frequency composition and size) is placed on respectively to driver's auris dextra place and all the other occupant's auris dextra places in car, carry out the Noise Acquisition under car load stationary state, each position is at least carried out above collection 3 times, extracts the noise rating number (NRN) certificate of full frequency band rate scope;

The 3rd step, the test of complete vehicle structure-acoustic transfer function;

(1) microphone speaker is arranged in to driver and each occupant's ears place in car;

(2) firmly hammer (can send the noise device of different frequency composition and size) is tested respectively suspend Partner, the structure-acoustic transfer function of exhaust lifting lug Partner to microphone in car, extracts the noise rating number (NRN) certificate of full frequency band rate scope;

The 4th step, internal car noise source contribution amount is identified fast;

(1) calculate the air radiation sound of internal car noise under vehicle acceleration mode, the mathematic(al) representation in airborne noise source:

$P_{\mathrm{air}}=\underset{j}{\overset{n}{\mathrm{\Σ}}}[p_j\left(f\right)-{\left(H\left(f\right)\right)}_j]---\left(1\right)$

In formula, P _airfor the air-borne sound summation of a certain specified point in car, j is noise source, and f is frequency, and n is the quantity of noise source and respective channel, p _j(f) be the noise sound of a certain noise source j, (H (f)) _j: be the sound transmission loss of a certain noise source j to specified point in car;

(2) calculate the structure-borne sound of internal car noise under vehicle acceleration mode, its mathematic(al) representation:

$P_{\mathrm{struct}}=\underset{k}{\overset{m}{\mathrm{\Σ}}}[F_k\left(f\right)-{\left(H\left(f\right)\right)}_k]---\left(2\right)$

In formula, P _structfor the structure-borne sound summation of a certain specified point in car, k is vibration source, and f is frequency, and m is the quantity of vibration source and respective channel, F _k(f) be the power value of a certain vibration source k, (H (f)) _kfor a certain vibration source k is to the sound of specified point in the car transport function of shaking;

(3) noise and vibration contribution amount model, integrated noise, vibration source, by formula (1), (2) can obtain:

P(f)=P _air+P _struct （3）

$P\left(f\right)=\underset{j}{\overset{n}{\mathrm{\Σ}}}[p_j\left(f\right)-{\left(H\left(f\right)\right)}_j]+\underset{k}{\overset{m}{\mathrm{\Σ}}}{[F_k\left(f\right)-{\left(H\left(f\right)\right)}_k]}_k---\left(4\right)$

The 5th step, the simplification stack based on order analysis;

To the noise source data that obtained, transfer function data, carries out the discrete of rotating speed and order by Frequency point, by subtracting each other, obtains the noise data of the interior corresponding rotating speed of car and order, obtains result as follows:

$P_{n_i{o}_j}=S_{n_i{o}_j}-H_{n_i{o}_j}---\left(5\right)$

In formula: n _ifor a certain rotating speed, o _jfor a certain order, for noise source value corresponding to certain rotating speed order, for transport function corresponding under rotating speed order,

the internal car noise value obtaining for calculating correspondence;

Utilize formula (6):

obtain the noise data of the interior corresponding rotating speed of car and order:

$P\left(f\right)=\mathrm{\Σ}{P}_{n_i{o}_j}---\left(6\right).$

Beneficial effect of the present invention: can identify fast Main Noise Sources and main bang path in car, provide reliable solution for solving internal car noise, shorten sense cycle, reduce auto NVH R&D costs.

Accompanying drawing explanation

Fig. 1 is noise source and the channel pattern of automobile.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail:

As shown in Figure 1, when carrying out the component analysis of internal car noise source contribution, need to calculate the excitation size of noise source, as air sound source: the wind (Q that makes an uproar ₁), tire radiated noise (Q ₂), power assembly radiated noise (Q ₃), porting radiated noise (Q ₄), intake and exhaust housing radiated noise (Q ₅), structure sound source: vibration input (F suspends ₁), hanger vibration input (F ₂), suspension vibration input (F ₃), other vibration input (F ₄);

Also need to obtain each noise source and be delivered to the noise transfer function in car, as air sound source transport function: car body outside surface is to passage (P _air1/ Q ₁), tire is around to passage (P _air2/ Q ₂), power assembly is to passage (P _air3/ Q ₃), porting is to passage (P _air4/ Q ₄), intake and exhaust housing is to passage (P _air5/ Q ₅), structure sound source transport function: suspend by car body to passage (P _in1/ F ₁), intake and exhaust hanger by car body to passage (P _in2/ F ₂), suspension by car body to passage (P _in3/ F ₃), other vibration by drag-line etc. to passage (P _in4/ F ₄);

By each sound source excitation of obtaining and each sound source, to the bang path function in car, try to achieve airborne noise P in car _airwith car inner structure noise P _struct, finally calculate total noise P in car _in.

Concrete test analysis step is as follows:

Of the present invention a kind of based on the discrete internal car noise source contribution amount method for quickly identifying of order, comprise the steps:

The first step, the collection of full load acceleration noise vibration;

(1) sensor is arranged in to driver and each occupant's ears place, nacelle six surfaces, portings, the main quilt that suspends moved end and exhaust lifting lug main quilt moved end in car; The microphone (microphone) that makes to be arranged in car is 10cm ± 1cm with the distance of backrest, and in same level height; Make to be arranged in the positional distance Engine Surface 10cm ± 1cm of the microphone in nacelle; Make to be arranged in the microphone at air intake opening place and the distance of air intake opening is 15cm, and microphone is over against air intake opening; Making to be arranged in the microphone of exhausr port and the distance of exhausr port is 50cm, and the axis of reference of microphone should be parallel to the ground, and and by the plane of exhausr port airflow direction and vertical ground at 45 ° ± angle of 10 °;

(2) carry out the collection of second gear full throttle acceleration noise, at least carry out above collection 3 times, extract full band frequency range noise Value Data;

Second step, car load sound transmission loss (TL) test;

(1) by microphone arrangement driver and each occupant's ears place, six surfaces of nacelle, porting in car; Making to be arranged in microphone in car and the distance of backrest is 10cm ± 1cm, and in same level height; Make to be arranged in the positional distance Engine Surface 10cm ± 1cm of the microphone in nacelle; Make to be arranged in the microphone at air intake opening place and the distance of air intake opening is 15cm, and microphone is over against air intake opening; Making to be arranged in the microphone of exhausr port and the distance of exhausr port is 50cm, and the axis of reference of microphone should be parallel to the ground, and and by the plane of exhausr port airflow direction and vertical ground at 45 ° ± angle of 10 °;

(2) volume sound source is placed on respectively to driver's auris dextra place and all the other occupant's auris dextra places in car, carries out the Noise Acquisition under car load stationary state, each position is at least carried out above collection 3 times, extracts the noise rating number (NRN) certificate of full frequency band rate scope;

The 3rd step, the test of complete vehicle structure-acoustic transfer function;

(1) microphone speaker is arranged in to driver and each occupant's ears place in car;

(2) firmly hammer is tested respectively suspend Partner, the structure-acoustic transfer function of exhaust lifting lug Partner to microphone in car, extracts the noise rating number (NRN) certificate of full frequency band rate scope;

The 4th step, internal car noise source contribution amount is identified fast;

(1) calculate the air radiation sound of internal car noise under vehicle acceleration mode, the mathematic(al) representation in airborne noise source:

$P_{\mathrm{air}}=\underset{j}{\overset{n}{\mathrm{\Σ}}}[p_j\left(f\right)-{\left(H\left(f\right)\right)}_j]---\left(1\right)$

In formula, P _airfor the air-borne sound summation of a certain specified point in car, j is noise source, and f is frequency, and n is the quantity of noise source and respective channel, p _j(f) be the noise sound of a certain noise source j, (H (f)) _j: be the sound transmission loss of a certain noise source j to specified point in car;

(2) calculate the structure-borne sound of internal car noise under vehicle acceleration mode, its mathematic(al) representation:

$P_{\mathrm{struct}}=\underset{k}{\overset{m}{\mathrm{\Σ}}}[F_k\left(f\right)-{\left(H\left(f\right)\right)}_k]---\left(2\right)$

In formula, P _structfor the structure-borne sound summation of a certain specified point in car, k is vibration source, and f is frequency, and m is the quantity of vibration source and respective channel, F _k(f) be the power value of a certain vibration source k, (H (f)) _kfor a certain vibration source k is to the sound of specified point in the car transport function of shaking;

(3) noise and vibration contribution amount model, integrated noise, vibration source, by formula (1), (2) can obtain:

P(f)=P _air+P _struct （3）

$P\left(f\right)=\underset{j}{\overset{n}{\mathrm{\Σ}}}[p_j\left(f\right)-{\left(H\left(f\right)\right)}_j]+\underset{k}{\overset{m}{\mathrm{\Σ}}}{[F_k\left(f\right)-{\left(H\left(f\right)\right)}_k]}_k---\left(4\right)$

The 5th step, the simplification stack based on order analysis;

To the noise source data that obtained, transfer function data, carries out the discrete of rotating speed and order by Frequency point, by subtracting each other, obtains the noise data of the interior corresponding rotating speed of car and order, obtains result as follows:

$P_{n_i{o}_j}=S_{n_i{o}_j}-H_{n_i{o}_j}---\left(5\right)$

In formula: n _ifor a certain rotating speed, o _jfor a certain order,

for noise source value corresponding to certain rotating speed order,

for transport function corresponding under rotating speed order,

the internal car noise value obtaining for calculating correspondence;

Utilize formula (6):

obtain the noise data of the interior corresponding rotating speed of car and order:

$P\left(f\right)=\mathrm{\Σ}{P}_{n_i{o}_j}---\left(6\right).$

Claims (1)

1. based on the discrete internal car noise source contribution amount method for quickly identifying of order, comprise the steps:

The first step, the collection of full load acceleration noise vibration;

(1) sensor is arranged in to driver and each occupant's ears place, nacelle six surfaces, portings, the main quilt that suspends moved end and exhaust lifting lug main quilt moved end in car; Making to be arranged in microphone in car and the distance of backrest is 10cm ± 1cm, and in same level height; Make to be arranged in the positional distance Engine Surface 10cm ± 1cm of the microphone in nacelle; Make to be arranged in the microphone at air intake opening place and the distance of air intake opening is 15cm, and microphone is over against air intake opening; Making to be arranged in the microphone of exhausr port and the distance of exhausr port is 50cm, and the axis of reference of microphone should be parallel to the ground, and and by the plane of exhausr port airflow direction and vertical ground at 45 ° ± angle of 10 °;

(2) carry out the collection of second gear full throttle acceleration noise, at least carry out above collection 3 times, extract full band frequency range noise Value Data;

Second step, the test of car load sound transmission loss;

(1) by microphone arrangement driver and each occupant's ears place, six surfaces of nacelle, porting in car; Making to be arranged in microphone in car and the distance of backrest is 10cm ± 1cm, and in same level height; Make to be arranged in the positional distance Engine Surface 10cm ± 1cm of the microphone in nacelle; Make to be arranged in the microphone at air intake opening place and the distance of air intake opening is 15cm, and microphone is over against air intake opening; Making to be arranged in the microphone of exhausr port and the distance of exhausr port is 50cm, and microphone direction should be parallel to the ground, and and by the plane of exhausr port airflow direction and vertical ground at 45 ° ± angle of 10 °;

(2) volume sound source is placed on respectively to driver's auris dextra place and all the other occupant's auris dextra places in car, carries out the Noise Acquisition under car load stationary state, each position is at least carried out above collection 3 times, extracts the noise rating number (NRN) certificate of full frequency band rate scope;

The 3rd step, the test of complete vehicle structure-acoustic transfer function;

(1) microphone speaker is arranged in to driver and each occupant's ears place in car;

(2) firmly hammer is tested respectively suspend Partner, the structure-acoustic transfer function of exhaust lifting lug Partner to microphone in car, extracts the noise rating number (NRN) certificate of full frequency band rate scope;

The 4th step, internal car noise source contribution amount is identified fast;

(1) calculate the air radiation sound of internal car noise under vehicle acceleration mode, the mathematic(al) representation in airborne noise source:

$P_{\mathrm{air}}=\underset{j}{\overset{n}{\mathrm{\Σ}}}[p_j\left(f\right)-{\left(H\left(f\right)\right)}_j]---\left(1\right)$

In formula, P _airfor the air-borne sound summation of a certain specified point in car, j is noise source, and f is frequency, and n is the quantity of noise source and respective channel, p _j(f) be the noise sound of a certain noise source j, (H (f)) _j: be the sound transmission loss of a certain noise source j to specified point in car;

(2) calculate the structure-borne sound of internal car noise under vehicle acceleration mode, its mathematic(al) representation:

$P_{\mathrm{struct}}=\underset{k}{\overset{m}{\mathrm{\Σ}}}[F_k\left(f\right)-{\left(H\left(f\right)\right)}_k]---\left(2\right)$

In formula, P _structfor the structure-borne sound summation of a certain specified point in car, k is vibration source, and f is frequency, and m is the quantity of vibration source and respective channel, F _k(f) be the power value of a certain vibration source k, (H (f)) _kfor a certain vibration source k is to the sound of specified point in the car transport function of shaking;

(3) noise and vibration contribution amount model, integrated noise, vibration source, by formula (1), (2) can obtain:

P(f)＝P _air+P _struct （3）

$P_{\left(f\right)}=\underset{j}{\overset{n}{\mathrm{\Σ}}}[p_j\left(f\right)-{\left(H\left(f\right)\right)}_j]+\underset{k}{\overset{m}{\mathrm{\Σ}}}[F_k\left(f\right)-{\left(H\left(f\right)\right)}_k]---\left(4\right)$

The 5th step, the simplification stack based on order analysis;

To the noise source data that obtained, transfer function data, carries out the discrete of rotating speed and order by Frequency point, by subtracting each other, obtains the noise data of the interior corresponding rotating speed of car and order, obtains result as follows:

$P_{n_i{o}_j}=S_{n_i{o}_j}-H_{n_i{o}_j}---\left(5\right)$

In formula: n _ifor a certain rotating speed, o _jfor a certain order,

for noise source value corresponding to certain rotating speed order,

for transport function corresponding under rotating speed order,

the internal car noise value obtaining for calculating correspondence;

Utilize formula (5):

obtain the noise data of the interior corresponding rotating speed of car and order:

$P\left(f\right)=\mathrm{\Σ}{P}_{n_i{o}_j}---\left(6\right).$

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