Method and system for determining vehicle sound insulation contribution

Abstract

The present invention discloses a method for determining the sound insulation contribution of a whole vehicle, comprising the following steps: 1) fully covering and wrapping the inner surface of the vehicle; 2) exciting a sound source in the passenger compartment to obtain the 1 / 3 octave received at different positions of the whole vehicle; 3) removing the sound insulation material of only one inner surface area of ​​the vehicle each time, and repeating step 2); 4) the sound insulation contribution of each inner surface area of ​​the vehicle at different positions of the whole vehicle. The present invention also discloses a system for determining the sound insulation contribution of a whole vehicle, comprising a sound source, a control unit, and a sound receiver; the sound source is placed at the position of the human ear in the passenger compartment, the sound receiver is used to receive the 1 / 3 octave at different positions of the whole vehicle, and the control unit is used to obtain the sound insulation contribution of each inner surface area of ​​the vehicle at different positions of the whole vehicle. The present invention can quickly and accurately obtain the contribution of each component of the whole vehicle to the sound insulation when passing through different transmission paths, which is conducive to quickly determining the weak positions of sound insulation for optimization and improvement.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile noise reduction, and in particular to a method and system for determining the sound insulation contribution of a whole vehicle. Background Art

[0002] With the development of the automobile industry, the noise level inside the car, as an important indicator for comfort evaluation, has attracted the attention of many consumers. Vehicle sound insulation is the most direct and effective way to reduce the noise level inside the car. By using sound insulation materials to isolate the sound source from the cabin, the noise radiation into the cabin is controlled, and a quiet driving environment is finally obtained. Therefore, adopting a reasonable vehicle sound insulation design is a key measure to improve the noise inside the car, and the vehicle sound insulation contribution test is an important means to verify and improve the vehicle sound insulation design.

[0003] Chinese patent CN108132159A discloses a system and method for identifying the noise contribution of automobile body sheet metal to the driving position in the car. It includes S1, controlling the sound source to emit low-frequency white noise, the sound source is placed at the driving position of the tested car, and the windows and doors of the tested car are kept in a closed state; S2, the vibration sensor collects the transfer function of the sheet metal position, and sends the collected transfer function to the FFT analysis software, the vibration sensor is set at the measured position of the body sheet metal; S3, the FFT analysis software identifies and displays the peak value of the transfer function. The above scheme obtains the contribution of each sheet metal part to noise transmission, rather than the sound insulation contribution. It is more complicated to obtain the transfer function using FFT analysis. The transfer function cannot intuitively measure the size of the noise received by the human ear, and the contribution at each noise frequency cannot be obtained. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a method and system for determining the sound insulation contribution of a whole vehicle, which can quickly and accurately obtain the contribution of each component of the whole vehicle to the sound insulation when passing through different transmission paths, thereby facilitating the rapid determination of weak sound insulation locations for optimization and improvement.

[0005] To achieve the above object, the present invention provides a method for determining the sound insulation contribution of a whole vehicle, comprising the following steps:

[0006] 1) Remove the interior trim of the car and use multiple pieces of sound insulation material to fully cover multiple areas of the interior surface of the car;

[0007] 2) Excite the sound source at the human ear position in the passenger compartment, measure and obtain the 1 / 3 octave frequency band received at different vehicle positions;

[0008] 3) Remove the sound insulation material of one vehicle interior surface area, repeat step 2), install the sound insulation material that was removed last time and remove the sound insulation material of the next vehicle interior surface area, repeat step 2), until the sound insulation materials of all vehicle interior surface areas have been removed once;

[0009] 4) Obtain the sound insulation contribution D(x) of each interior surface area at different vehicle positions i ,y j )-D(x0,y j ), then the sound insulation contribution of each interior surface area at different vehicle positions η(x i ,y j )for

[0010]

[0011] Where D is 1 / 3 octave, unit is dB, η is the sound insulation contribution, x i is the i-th car interior surface area, i is the division number of each car interior surface area, x0 is the car interior surface when the sound insulation material is fully covered, y j is the jth vehicle position, and each j is the division number of the vehicle position.

[0012] Furthermore, in step 2), the sound source is excited at different frequencies to obtain the 1 / 3 octave frequency band D(x i ,y j ,z k ), and obtain the sound insulation contribution D(x i ,y j ,z k )-D(x0,y j ,z k ), the sound insulation contribution η(x i ,y j ,z k )for

[0013]

[0014] In the formula, z k is the kth sound source frequency, and k is the number of different sound source frequencies.

[0015] Furthermore, the vehicle is parked in a semi-anechoic chamber with a signal-to-noise ratio of ≥20dB, the temperature of the semi-anechoic chamber is 20°C to 30°C, and the humidity is controlled at 30% to 90%.

[0016] Furthermore, the human ear positions in the passenger compartment include the front left ear, the front right ear, the rear left ear and the rear right ear, from which the human ear position in the passenger compartment closest to the position of the entire vehicle to be tested is selected for sound source excitation.

[0017] The present invention also provides a system based on the above-mentioned vehicle sound insulation contribution determination method, comprising a sound source, a control unit, and a sound receiver; the sound source is placed at the human ear position in the passenger compartment, the sound receiver is placed at different vehicle positions, and is used to receive the 1 / 3 octave frequency band at different vehicle positions, and the control unit is used to obtain the sound insulation contribution η(x) of each vehicle interior surface area at different vehicle positions according to the following formula i ,y j )

[0018]

[0019] Where D is 1 / 3 octave, unit is dB, η is the sound insulation contribution, x i is the i-th car interior surface area, i is the division number of each car interior surface area, x0 is the car interior surface when the sound insulation material is fully covered, y j is the jth vehicle position, and each j is the division number of the vehicle position.

[0020] Furthermore, the sound receiver is used to receive 1 / 3 octave D(x i ,y j ,z k ), the control unit is used to obtain the sound insulation contribution η(x) of each vehicle interior surface area at different sound source frequencies and different vehicle positions according to the following formula i ,y j ,z k )

[0021]

[0022] In the formula, z k is the kth sound source frequency, and k is the number of different sound source frequencies.

[0023] The beneficial effects of the present invention are as follows: by obtaining the sound insulation contribution of each vehicle interior surface area at different sound source frequencies and different vehicle positions, the degree of attenuation of the sound at different frequencies after passing through different transmission paths from the same vehicle part is quickly determined. The greater the sound insulation contribution, the greater the noise contribution transmitted by the area where the sound insulation material is removed, so that the sound insulation of the above-mentioned area is targetedly optimized during the forward design of the vehicle, thereby improving the sound insulation performance of the whole vehicle. DETAILED DESCRIPTION

[0024] The following specific implementations are used to further explain the technical solutions of the claims of the present invention in detail, so that those skilled in the art can more clearly understand the claims. The protection scope of the present invention is not limited to the following specific embodiments. The technical solutions of the claims of the present invention made by those skilled in the art but different from the following specific implementations are also within the protection scope of the present invention.

[0025] A vehicle sound insulation contribution determination system based on the above-mentioned system comprises a sound source, a control unit and a sound receiver; the sound source is placed at the position of the human ear in the passenger compartment, the sound receiver is a microphone and a sound processor, which are placed at different positions of the vehicle and are used to receive the 1 / 3 octave frequency band at different positions of the vehicle, and the control unit is used to obtain the sound insulation contribution η(x i ,y j )

[0026]

[0027] Where D is 1 / 3 octave, unit is dB, η is the sound insulation contribution, x i is the i-th car interior surface area, i is the division number of each car interior surface area, x0 is the car interior surface when the sound insulation material is fully covered, y j is the jth vehicle position, and each j is the division number of the vehicle position.

[0028] As a more preferred embodiment, the sound receiver is used to receive 1 / 3 octave D(x i ,y j ,z k ), the control unit is used to obtain the sound insulation contribution η(x i ,y j ,z k )

[0029]

[0030] In the formula, z k is the kth sound source frequency, and k is the number of different sound source frequencies.

[0031] The method for determining the whole vehicle sound insulation contribution using the above-mentioned whole vehicle sound insulation contribution determination system is as follows:

[0032] 1. Park the vehicle in a semi-anechoic chamber with a signal-to-noise ratio of ≥20dB, the temperature of the semi-anechoic chamber is 20℃~30℃, and the humidity is controlled at 30%~90%. Remove the interior decoration parts of the vehicle, use multiple pieces of sound insulation materials to fully cover multiple areas of the vehicle surface, and conduct an air tightness test on the whole vehicle to ensure that the sample vehicle has good air tightness.

[0033] 2. Perform sound source excitation at the human ear position in the passenger compartment, measure and obtain the 1 / 3 octave frequency band received at different vehicle positions. The human ear positions in the passenger compartment include the front left ear, front right ear, rear left ear and rear right ear. Select the human ear position in the passenger compartment closest to the vehicle position to be measured for sound source excitation. The sound source positions corresponding to each vehicle position are shown in Table 1.

[0034] Table 1 Sound source positions corresponding to different vehicle positions

[0035]

[0036] 3. Remove the sound insulation material of one vehicle interior surface area, repeat step 2, install the sound insulation material that was removed last time and remove the sound insulation material of the next vehicle interior surface area, repeat step 2 until the sound insulation materials of all vehicle interior surface areas have been removed once. The orthogonal test of 1 / 3 octave frequency band collected at different vehicle positions under different vehicle interior surface areas is shown in Table 2, among which the full coverage wrapping is the operation process in step 2.

[0037] Table 2 1 / 3 octave frequency bands at different vehicle positions in different vehicle interior surface areas

[0038]

[0039]

[0040] 4. Obtain the sound insulation contribution D(x i ,y j )-D(x0,y j ), then the sound insulation contribution of each interior surface area at different vehicle positions η(x i ,y j )for

[0041]

[0042] Where D is 1 / 3 octave, unit is dB, η is the sound insulation contribution, x i is the i-th car interior surface area, i is the division number of each car interior surface area, x0 is the car interior surface when the sound insulation material is fully covered, y j is the jth vehicle position, and each j is the division number of the vehicle position.

[0043] As a more preferred embodiment, in step 2), the sound source is further excited at different frequencies to obtain the 1 / 3 octave frequency band D(x i ,y j ,z k), and obtain the sound insulation contribution D(x i ,y j ,z k )-D(x0,y j ,z k ), the sound insulation contribution η(x i ,y j ,z k )for

[0044]

[0045] In the formula, z k is the kth sound source frequency, and k is the number of different sound source frequencies.

[0046] In this embodiment, the sound source frequencies include 250 Hz, 315 Hz, 400 Hz, 500 Hz, 630 Hz, 800 Hz, 1000 Hz, 1250 Hz, 1600 Hz, 2000 Hz, 2500 Hz, 3150 Hz, 4000 Hz and total level.

[0047] The present invention obtains the sound insulation contribution of each vehicle interior surface area at different sound source frequencies and different vehicle positions, thereby quickly determining the degree of attenuation of sound at different frequencies after passing through different transmission paths from the same vehicle part. The greater the sound insulation contribution, the greater the noise contribution transmitted by the area where the sound insulation material is removed, so that the sound insulation of the above area is targetedly optimized during the forward design of the vehicle, thereby improving the sound insulation performance of the whole vehicle.

Claims

1. A method for determining the sound insulation contribution of a whole vehicle, characterized in that: The steps include: 1) Remove the interior trim of the car and use multiple pieces of sound insulation material to fully cover multiple areas of the interior surface of the car; 2) Excite the sound source at the human ear position in the passenger compartment, measure and obtain the 1 / 3 octave frequency band received at different vehicle positions; 3) Remove the sound insulation material of one vehicle interior surface area, repeat step 2), install the sound insulation material that was removed last time and remove the sound insulation material of the next vehicle interior surface area, repeat step 2), until the sound insulation materials of all vehicle interior surface areas have been removed once; 4) Obtain the sound insulation contribution D(x) of each interior surface area at different vehicle positions i ,y j )-D(x0,y j ), then the sound insulation contribution of each interior surface area at different vehicle positions η(x i ,y j )for Where D is 1 / 3 octave, unit is dB, η is the sound insulation contribution, x i is the i-th car interior surface area, i is the division number of each car interior surface area, x0 is the car interior surface when the sound insulation material is fully covered, y j is the jth vehicle position, and each j is the division number of the vehicle position; In step 2), the sound source is also excited at different frequencies to obtain the 1 / 3 octave frequency band D(x i ,y j ,z k ), and obtain the sound insulation contribution D(x i ,y j ,z k )-D(x0,y j ,z k ), the sound insulation contribution η(x i ,y j ,z k )for In the formula, z k is the kth sound source frequency, and k is the number of different sound source frequencies.

2. The method for determining the vehicle sound insulation contribution according to claim 1, characterized in that: Park the vehicle in a semi-anechoic room with a signal-to-noise ratio ≥ 20dB. The temperature of the semi-anechoic room is 20℃~30℃ and the humidity is controlled at 30%~90%.

3. The method for determining the vehicle sound insulation contribution according to claim 1, characterized in that: The human ear positions in the passenger compartment include the front left ear, the front right ear, the rear left ear and the rear right ear, from which the human ear position in the passenger compartment closest to the position of the vehicle to be tested is selected for sound source excitation.

4. A system based on the method for determining the vehicle sound insulation contribution according to any one of claims 1 to 3, characterized in that: It includes a sound source, a control unit, and a sound receiver; the sound source is placed at the position of the human ear in the passenger compartment, the sound receiver is placed at different positions of the vehicle, and is used to receive the 1 / 3 octave frequency at different positions of the vehicle, and the control unit is used to obtain the sound insulation contribution η(x i ,y j ) Where D is 1 / 3 octave, unit is dB, η is the sound insulation contribution, x i is the i-th car interior surface area, i is the division number of each car interior surface area, x0 is the car interior surface when the sound insulation material is fully covered, y j is the jth vehicle position, and each j is the division number of the vehicle position; The sound receiver is used to receive 1 / 3 octave D(x i ,y j ,z k ), the control unit is used to obtain the sound insulation contribution η(x) of each vehicle interior surface area at different sound source frequencies and different vehicle positions according to the following formula i ,y j ,z k ) In the formula, z k is the kth sound source frequency, and k is the number of different sound source frequencies.

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