CN102494754A - 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 of automobile (noise and vibration) has become one of most important index in the automobile brand.Numerous auto vendors are the attraction core of excellent NVH performance as its product, and the automobile of excellent NVH performance is being represented brand's equity and meaning.How analyzing the NVH problem faster, find out and have weakness, form the through engineering approaches solution, is the key element that promotes the NVH performance.In to noise and vibration contribution quantitative analysis, to the identification of source and transport function, classic method adopts the discrete and integrated approach based on third-octave, and there is the frequency out of true in this kind method in the identification of construct noise, the problem that the order noise can't extract.Therefore, need seek approach in addition.

Summary of the invention

The purpose 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; This method can correctly be discerned each driving source and bang path thereof the size to the noise and vibration contribution amount fast when research car load internal car noise driving source and bang path thereof.

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) with transducer arrangements in car driver and each occupant's ears place, nacelle six surfaces, portings, main Partner and exhaust hanger master Partner suspend; Making the distance that is arranged in interior microphone (microphone) of car and backrest is 10cm ± 1cm, and is in same level height; Make the position that is arranged in the microphone in the nacelle apart from Engine Surface 10cm ± 1cm; Making the microphone that is arranged in the air intake opening place and the distance of air intake opening is 15cm, and microphone is over against air intake opening; Making the microphone that is arranged in exhausr port and the distance of exhausr port is 50cm, and the axis of reference of microphone should be parallel to the ground, and becomes 45 ° ± 10 ° angle with the plane through exhausr port airflow direction and vertical ground;

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

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

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

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

In the 3rd step, complete vehicle structure-acoustics passes the letter test;

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

(2) firmly hammer (can send the noise device of different frequency composition and size) is tested the Partner that suspends respectively, exhaust hanger Partner passes letter to structure-acoustics of microphone in the car, extracts the noise rating number (NRN) certificate of full frequency band rate scope;

The 4th step, internal car noise source contribution amount quick identification;

(1) the air radiation sound of noise in calculating vehicle acceleration mode is got off, 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 the formula, P _AirBe the air-borne sound summation of a certain specified point in the car, j is a noise source, and f is a 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 specified point to the car;

(2) structure-borne sound of noise in calculating vehicle acceleration mode is got off, 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 the formula, P _StructBe the air-borne sound summation of a certain specified point in the car, k is a vibration source, and f is a 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)) _kBe a certain vibration source k sound of specified point to the car transport function of shaking;

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

P(f)＝P _air+P _struct (3)

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

$P\left(f\right)=\underset{i}{\overset{n+m}{\mathrm{\Σ}}}{P}_i\left(f\right)---\left(5\right)$

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

To the noise source data that obtained, transfer function data is carried out the discrete of rotating speed and order by Frequency point, through subtracting each other, obtains the noise data of corresponding rotating speed and order in the car, and it is following to obtain the result:

$P_{n_i{o}_j}=S_{n_i{o}_j}-H_{n_i{o}_j}---\left(6\right)$

In the formula: n _iBe a certain rotating speed, o _jBe a certain order,

Be the corresponding noise source value of certain rotating speed order,

Be the corresponding down transport function of rotating speed order,

For calculating the internal car noise value that correspondence obtains; Utilize formula (6):

Obtain the noise data of corresponding rotating speed and order in the car:

$P\left(f\right)=\mathrm{\Σ}{P}_{n_i{o}_j}---\left(7\right)$

Beneficial effect of the present invention: overriding noise source and main bang path in can the quick identification car, for solving internal car noise reliable solution is provided, shortened sense cycle, reduced automobile NVH R&D costs.

Description of drawings

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

Embodiment

Below in conjunction with accompanying drawing and embodiment the present invention is done further explain:

By shown in Figure 1, when carrying out the component analysis of internal car noise source contribution, need calculate the excitation size of noise source, like the 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), the 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 obtain each noise source and be delivered to the noise transfer function in the car, like air sound source transport function: the car body outside surface is to passage (P _Air1/ Q ₁), around the tire to passage (P _Air2/ Q ₂), power assembly is to passage (P _Air3/ Q ₃), porting is to passage (P _Air4/ Q ₄), the intake and exhaust housing is to passage (P _Air5/ Q ₅), structure sound source transport function: suspend through car body to passage (P _In1/ F ₁), the intake and exhaust hanger through car body to passage (P _In2/ F ₂), suspension through car body to passage (P _In3/ F ₃), other vibration through drag-line etc. to passage (P _In4/ F ₄);

Through the bang path function in each sound source excitation of obtaining and each sound source to the car, try to achieve airborne noise P in the car _AirWith car inner structure noise P _Struct, calculate noise P total in the car at last _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) with transducer arrangements in car driver and each occupant's ears place, nacelle six surfaces, portings, main Partner and exhaust hanger master Partner suspend; Making the distance that is arranged in interior microphone (microphone) of car and backrest is 10cm ± 1cm, and is in same level height; Make the position that is arranged in the microphone in the nacelle apart from Engine Surface 10cm ± 1cm; Making the microphone that is arranged in the air intake opening place and the distance of air intake opening is 15cm, and microphone is over against air intake opening; Making the microphone that is arranged in exhausr port and the distance of exhausr port is 50cm, and the axis of reference of microphone should be parallel to the ground, and becomes 45 ° ± 10 ° angle with the plane through exhausr port airflow direction and vertical ground;

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

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

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

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

In the 3rd step, complete vehicle structure-acoustics passes the letter test;

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

(2) firmly hammer is tested the Partner that suspends respectively, exhaust hanger Partner passes letter to structure-acoustics of microphone in the car, extracts the noise rating number (NRN) certificate of full frequency band rate scope;

The 4th step, internal car noise source contribution amount quick identification;

(1) the air radiation sound of noise in calculating vehicle acceleration mode is got off, 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 the formula, P _AirBe the air-borne sound summation of a certain specified point in the car, j is a noise source, and f is a 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 specified point to the car;

(2) structure-borne sound of noise in calculating vehicle acceleration mode is got off, 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 the formula, P _StructBe the air-borne sound summation of a certain specified point in the car, k is a vibration source, and f is a 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)) _kBe a certain vibration source k sound of specified point to the car transport function of shaking;

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

P(f)＝P _air+P _struct (3)

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

$P\left(f\right)=\underset{i}{\overset{n+m}{\mathrm{\Σ}}}{P}_i\left(f\right)---\left(5\right)$

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

To the noise source data that obtained, transfer function data is carried out the discrete of rotating speed and order by Frequency point, through subtracting each other, obtains the noise data of corresponding rotating speed and order in the car, and it is following to obtain the result:

$P_{n_i{o}_j}=S_{n_i{o}_j}-H_{n_i{o}_j}---\left(6\right)$

In the formula: n _iBe a certain rotating speed, o _jBe a certain order,

Be the corresponding noise source value of certain rotating speed order,

Be the corresponding down transport function of rotating speed order,

For calculating the internal car noise value that correspondence obtains; Utilize formula (6):

Obtain the noise data of corresponding rotating speed and order in the car:

$P\left(f\right)=\mathrm{\Σ}{P}_{n_i{o}_j}---\left(7\right).$

Claims (1)

1. an internal car noise source contribution amount method for quickly identifying that disperses based on order comprises the steps:

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

(1) with transducer arrangements in car driver and each occupant's ears place, nacelle six surfaces, portings, main Partner and exhaust hanger master Partner suspend; Making the microphone that is arranged in the car and the distance of backrest is 10cm ± 1cm, and is in same level height; Make the position that is arranged in the microphone in the nacelle apart from Engine Surface 10cm ± 1cm; Making the microphone that is arranged in the air intake opening place and the distance of air intake opening is 15cm, and microphone is over against air intake opening; Making the microphone that is arranged in exhausr port and the distance of exhausr port is 50cm, and the axis of reference of microphone should be parallel to the ground, and becomes 45 ° ± 10 ° angle with the plane through exhausr port airflow direction and vertical ground;

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

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

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

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

In the 3rd step, complete vehicle structure-acoustics passes the letter test;

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

(2) firmly hammer is tested the Partner that suspends respectively, exhaust hanger Partner passes letter to structure-acoustics of microphone in the car, extracts the noise rating number (NRN) certificate of full frequency band rate scope;

The 4th step, internal car noise source contribution amount quick identification;

(1) the air radiation sound of noise in calculating vehicle acceleration mode is got off, 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 the formula, P _AirBe the air-borne sound summation of a certain specified point in the car, j is a noise source, and f is a 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 specified point to the car;

(2) structure-borne sound of noise in calculating vehicle acceleration mode is got off, 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 the formula, P _StructBe the air-borne sound summation of a certain specified point in the car, k is a vibration source, and f is a 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)) _kBe a certain vibration source k sound of specified point to the car transport function of shaking;

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

P(f)＝P _air+P _struct (3)

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

$P\left(f\right)=\underset{i}{\overset{n+m}{\mathrm{\Σ}}}{P}_i\left(f\right)---\left(5\right)$

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

To the noise source data that obtained, transfer function data is carried out the discrete of rotating speed and order by Frequency point, through subtracting each other, obtains the noise data of corresponding rotating speed and order in the car, and it is following to obtain the result:

$P_{n_i{o}_j}=S_{n_i{o}_j}-H_{n_i{o}_j}---\left(6\right)$

In the formula: n _iBe a certain rotating speed, o _jBe a certain order,

Be the corresponding noise source value of certain rotating speed order, Be the corresponding down transport function of rotating speed order,

Utilize formula (6) for calculating the internal car noise value that correspondence obtains:

Obtain the noise data of corresponding rotating speed and order in the car:

$P\left(f\right)=\mathrm{\Σ}{P}_{n_i{o}_j}---\left(7\right).$

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