GB 1495-2002 Limits and measurement methods for noise outside the vehicle during acceleration GB1495-2002 standard download decompression password: www.bzxz.net

ICS _13. 140
National Standard of the People's Republic of China
GB1495-.2002
Replaces G1495-79. Partially replaces G131496-79
Limits and measurement methods for noise emitted by accelerating motor vehicles Issued on January 4, 2002
State Environmental Protection Administration
General Administration of Quality Supervision, Inspection and Quarantine
2002-10-01 Implementation
GB14952002
This standard is formulated in accordance with the Law of the People's Republic of China on the Prevention and Control of Environmental Noise Pollution. This standard is formulated with reference to the United Nations Economic Commission for Europe Regulation ECE Reg. No. 51 on the Uniform Provisions for Type Approval of Motor Vehicles (with at least 4 wheels) in terms of Noise, and is based on the actual situation of my country's automobile products. The noise limits of this standard replace the automobile noise limits in GB1495-79. The technical content of the noise production measurement method of this standard refers to the Annex 3 of the United Nations Economic Commission for Europe Regulation ECE Reg. No. 51/02 (1997) on the "Uniform Provisions for Type Approval of Automobiles (with at least four wheels) in terms of noise" and the corresponding content in the international standard ISO3621998 "Acoustic Road Vehicle Acceleration Noise Measurement Method Engineering Method". The requirements for test road surfaces in this standard are equivalent to those in 1S010844: 1994 "Provisions for Test Road Surfaces for Acoustic Measurement of Road Vehicle Noise", and will be implemented from January 1, 2005. This standard is based on This standard is proposed by the Science and Technology Standards Department of the State Environmental Protection Administration. This standard was drafted by the Beijing Labor Protection Science Research Institute and the China Automotive Technology Research Center. This standard was approved by the State Environmental Protection Administration on November 22, 2001. This standard is subject to the interpretation of the State Environmental Protection Administration. 120
1 Scope
Limits and measurement methods for the noise level outside the vehicle when the vehicle is accelerating This standard specifies the limits for the noise level outside the vehicle when the vehicle is accelerating. This standard specifies the measurement method for the noise level outside the vehicle when the vehicle is accelerating. This standard applies to M and N' class vehicles. 2 Referenced standards
GB1495—2002
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is revised, the versions shown are valid. All standards will be revised, and the parties using this standard should consider the possibility of using the latest versions of the following standards. GB/T378-1983 Electrical and acoustic properties and test methods of sound level meters GB/T15173-1994 Sound calibrator
GB/T12534--1990 General rules for road test methods for automobiles ISO 10844:1994 Acoustics - Provisions for test pavement for measuring road vehicle noise 3) 1S010534:1996 Acoustics - Determination of sound absorption coefficient and impedance standing wave method using impedance tube GB/T17692-1999 Test method for net engine power of automobiles 3 Definitions
This standard adopts the following definitions,
3.1 Vehicle type
In terms of exterior noise, a vehicle type refers to a class of vehicles that do not differ in the following main aspects: 3.1.1 Body shape or structural materials (especially engine 3.1.2 Vehicle length and width:
3.1.3 Engine type (sparking or compression ignition, two-stroke or four-stroke, reciprocating or rotary), number of cylinders and displacement, number and type of carburetors or type of fuel injection system, valve arrangement, rated power and corresponding speed; or type of drive motor (for electric vehicles:
3.1.4 Transmission system, number of gears and their speed ratios, 3.1.5 Noise reduction systems or components as defined in 3.2 and 3.3 below. 3.1.6 Vehicles other than those of category M and N, with the same type of engine and/or different total transmission ratios, may be considered the same vehicle type if the differences in 3.1.2 and 3.1.4 do not result in changes in the noise measurement method (such as gear selection). 3.2 Noise reduction system
The noise reduction system refers to the complete set of components necessary to limit the noise of the vehicle and its exhaust. When the noise reduction components in the system have different brands or trademarks. Or the size and shape of the components, material properties, assembly, working principle, or the number of intake/exhaust mufflers are different, the system should be regarded as a different type of noise reduction system. bzxZ.net
1) Classification of vehicles R15089·1994 Regulations on the classification of motor vehicles 2) 3) This standard is under the jurisdiction of the National Committee for Technical Standardization. 121
GB 1495—2002
3. 3 Noise reduction system components
Noise reduction system components refer to one of the individual components that constitute the noise reduction system, such as exhaust pipe, expansion chamber, muffler, etc. When the presence of the air filter is necessary to ensure that the specified noise limit is met, it is considered to be a component of the noise reduction system, and the exhaust manifold is not considered to be a component of the noise reduction system.
3.4Back noise
Background noise refers to the noise of the surrounding environment (including wind noise) when the noise of the tested car does not exist. 3.5Rated power
The rated power of the engine refers to the net power expressed in kW measured by the force measurement method specified in GB/T17692. 4Noise limit
When the car is accelerating, its maximum noise level outside the car should not exceed the limit specified in Table 1. The meanings of the symbols in the table are as follows:
Maximum total mass (t);
Rated power of the engine (kW)
External noise limit of luxury car accelerating
Noise limit/dB(A)
Automobile classification
M(GVM≤3.60. or N,(GVM≤3.5t)
21≤GVM≤3.5t
Ma.515t)
P150kW
P150kw
N(3.2 t. If P 150 kW, the limit value is increased by 1 dB(A); if P 150 kW+, the limit value is increased by 2B(A).
M, if the transmission has more than four forward gears, P>140 kW, the ratio of P/GVM is greater than 75 kW/t, and the speed of the end outlet when tested in the third gear is greater than 61 km/h+, the limit value is increased by 1 dB(A). 5 Measurement method
The measurement of the exterior noise of the vehicle when accelerating shall be carried out in accordance with Appendix A. 122
A1 Measuring instruments
A1.1 Acoustic measurement
Appendix A
(Standard Appendix)
Method for measuring the exterior noise of the vehicle when accelerating GB 1495--2002
A1.1.1 The sound level meter or other equivalent measurement system used for measurement shall not be lower than the requirements of Type 1 sound level meter specified in GB3785. The "A" frequency weighting characteristic and "F" time weighting characteristic should be used during measurement. When using a system that can automatically sample and measure the A-weighted sound level, the reading interval should not be greater than 0 ms.
A1.1.2 Before and after measurement, the sound level meter must be calibrated according to the manufacturer's regulations using a Class 1 sound calibrator that complies with GB/T151.73. Without any further adjustment, if the difference between the last calibration reading and the previous calibration reading exceeds 0.5 dB, the measurement result after the previous calibration is considered invalid. The calibration readings should be recorded in the table in Appendix AB. A1.2 Rotation speed and vehicle speed measurement
An engine tachometer or vehicle speed measuring instrument with an accuracy better than ±2 must be used to monitor the rotation speed or vehicle speed. Similar instruments on the car must not be used.
A1.3 Measurement of meteorological parameters
The accuracy of the thermometer should be within ±1°C. The accuracy of the anemometer should be within ±1.0m/s. A1.4 All measuring instruments shall be inspected regularly in accordance with the relevant national regulations on measuring instruments. A2 Measurement conditions
A2.1 Measurement site
A2.1.1 The sound field conditions that the measurement site (see Figure 1) should meet are: when a non-directional small sound source is placed at the center of the site (point 0), the sound level deviation in all directions on the hemisphere does not exceed ±1B. If the following conditions are met, the site can be considered to have met this sound field condition: a) With the center of the measurement site (point O) as the base point, there are large sound reflectors such as fences, rocks, bridges or buildings within a radius of 50m; b) The test road surface and the rest of the site are dry, without snow, tall grass, loose soil or sound-absorbing materials such as slag; there are no obstacles that affect the sound field near the microphone, and no one stands between the sound source and the microphone. The observer who conducts the measurement should also stand in a position that will not affect the instrument measurement value. A2.1.2 The measurement site should be substantially level, solid and flat, and the test road surface should not generate excessive tire noise. The road surface should comply with the requirements of Annex AA.
A2.2 Meteorological
The test should be carried out in good weather. The wind speed at the microphone height should not exceed 5m/s during the measurement. Care must be taken that the measurement results are not affected by gusts. A suitable wind shield may be used, but its effect on the sensitivity and directivity of the microphone should be taken into account. The instrument for measuring meteorological parameters should be placed near the measurement site at a height of 1.2m. A2.3 Background noise
The background noise (A-weighted sound level) should be at least 10 lower than the noise of the vehicle being tested. A2.4 Vehicle
A2.4.1 The vehicle being tested should be unloaded, without trailer or semitrailer (except for non-decomposable vehicles). A2.4.2 The tires installed on the tested vehicle shall be selected by the vehicle manufacturer and must be of the type specified for the vehicle model. Any tire with a tread depth of less than 1.6 mm shall not be used. The tires must be inflated to a certain pressure under load. A2.4.3 Before starting the measurement, the technical condition of the tested vehicle shall comply with the technical conditions of the vehicle model (especially the acceleration performance of the vehicle) and the relevant provisions of GB 1495-2002 (313/2534) (including engine temperature, adjustment, fuel, spark plugs, etc.). A2.4.4 If the vehicle has two or more drive shafts, the measurement shall be carried out in the driving mode commonly used in road driving. A2.4.5 If the vehicle is equipped with a fan with an automatic drive mechanism, it shall remain in automatic operation during the measurement. If the vehicle is equipped with equipment such as a cement mixer, an air compressor (not for the brake system), etc., do not start the fan during the measurement. A3 Measurement method A3.1 Measurement area and microphone arrangement A3.1.1 Acceleration driving measurement area shall be determined according to Figure A1. Point 0 is the center of the measurement area, the length of the acceleration section is 2×(10m ± 0.05m), line AA' is the acceleration start line, line BB' is the acceleration end line. CC is the driving center line. A3.1.2 The microphone should be arranged at a height of 1.2m ± 0.02m above the ground and 7.5m + 0.05m from the driving center line CC. Its reference axis must be horizontal and vertical to the driving center line CC. A3.2 Determination of vehicle gear selection and approach speed The symbols used in this article have the following meanings:
S: rated speed of the engine;
NA: stable speed of the engine when approaching line AA'. 43.2.1.1 Gear selection a) For M1 and N2 class vehicles equipped with a transmission with no more than four forward gears, the measurement shall be made in the second gear; b) For M2 and N3 class vehicles equipped with a transmission with more than four forward gears, the measurement shall be made in the second and third gears respectively. If the engine speed exceeds S when the rear end of the vehicle passes the BB line when measuring in the first gear, N shall be reduced by 5% S step by step until the engine speed does not exceed 5 when passing the B' line. If N is reduced to a high speed and the speed still exceeds S when passing the B3 line, only the third gear shall be used for measurement. However, for M2 class vehicles with more than four forward gears and equipped with an engine with a rated power greater than 140 kW and a rated power/maximum gross mass ratio greater than 75 kW/t, if the speed of the rear end of the vehicle passing the BB line in the third gear is greater than 61 km/h, only the second gear shall be used for measurement.
GB1495—2002
c) For vehicles other than M, and N, with a total forward gear of X (including vehicles with a speed ratio > obtained by a sub-transmission or a multi-speed ratio drive axle, the measurement should be carried out using each gear equal to or greater than X/. For vehicles with an engine rated power not exceeding 225kW, take n=2. For vehicles with a rated power exceeding 225W, take n=3. If 1X/n is not an integer, the gear corresponding to the higher integer is selected. The measurement is carried out starting from the X/th gear and gradually increasing the gear until the rear end of the vehicle passes the BB' line in a certain gear. The engine speed is measured until the first time it drops below the rated speed. Note: If the main transmission has a speed ratio and the auxiliary transmission has two speed ratios, the transmission system has a total of 16 gears. If the rated power of the engine is 23kW, (X/n) = (8×2)/3 = 16/3-5%. The gear to be measured is the sixth gear (that is, the sixth of the 15 gears obtained by the combination of the main and auxiliary transmissions), and the next gear to be measured is the seventh gear, and so on. 43.2.1.2 Determination of approach speed
The stable speed when approaching the AA line is the smaller of the following speeds: H) 50knm/h;
b) For FM, and other types of vehicles with engine power not greater than 225kW: corresponding to a speed of 3/4S;
c) For all types of vehicles other than M, with engine power greater than 225kW: corresponding to a speed of 1/2S.
A3.2.2 Automatic transmission
A3.2.2.1 Position selection
If the vehicle's automatic transmission is equipped with a manual gear selector, the gear selector should be placed in the position recommended by the manufacturer for normal driving for measurement.
A3.2.2.2 Determination of closing speed
A3.2.2.2.1 For vehicles with a manual gear selector, the closing speed shall be in accordance with A5.2.1.2. If the vehicle's automatic transmission has two or more gears and it automatically shifts to a low gear specified by the manufacturer that is not used in normal urban driving (including gears for slow driving or braking) during the measurement, the following measures can be taken: a) Increase the approach speed to a maximum of 60 km/h to avoid shifting to the above-mentioned low gear; b) Maintain the approach speed at 50 km/h and limit the engine's fuel supply to 9.5% of the full load required during acceleration. The following operations can be considered to meet this condition:
For spark-ignition engines, open the throttle to 90% of the full opening angle; for compression-ignition engines, control the fuel injection position to 90% of its maximum fuel supply. ) Install an electronic control device to prevent shifting to the above-mentioned low gear. A3.2.2.2.2 For vehicles without a downshift selector, the vehicle should approach the AA line at a steady speed of 30, 40, and 50 km/h (if the vehicle's maximum speed on the road is 3/4 less than 50 km/h, then approach the AA line at a steady speed of 3/4 of its maximum speed). 43.3 Acceleration operation
A3.3.1 The vehicle should approach the AA line at the gear position and steady speed specified above, and its speed change should be controlled within 1 km/h; the engine speed should be controlled, and the speed change should be controlled within ±2% or ±50 r/min (the larger of the two). A3.3.2 When the front end of the vehicle reaches the AA line, the accelerator pedal must be pushed to the bottom as quickly as possible (i.e. the throttle or accelerator is fully open). Keep it unchanged until the rear end of the vehicle passes the BB' line, and then release the pedal as quickly as possible (i.e. the throttle or accelerator is closed). A3.3.3 The car should accelerate through the measurement area in a straight line, and its longitudinal center plane should be as close to the center line CC as possible. A3.3.4 If the vehicle consists of a tractor and a trailer that is not easily separated, the trailer shall not be considered when determining whether the rear end passes through the BB line. A3.4 Sound level measurement panel
A3.4.1 At least four measurements should be made on each side of the car. 43.4.2 The maximum sound level of the car accelerating through the measurement area should be measured. Each measured value should be subtracted by 1dB (A as the measurement result,
43.4.3 If the difference between the results of four consecutive measurements on the side of the car is not greater than 2B, the measurement result is considered valid. 125
GR1495—2002
A3.4.4 Take the arithmetic average of the four measurement results on each side under each gear (or approach speed) condition and then take the larger average value on both sides as the middle result.
A3.5* Determination of the maximum noise level of the automobile
A3.5.1 corresponds to the gear condition of a) in A3.2.1.1. Directly take the middle result as the maximum noise level. A3.5.2 corresponds to the gear condition of b) in A3.2.1.1. If the second and third gears are used for measurement, take the arithmetic average of the results between the two gears as the maximum noise level. If only the third gear is used for measurement, the middle result of that gear shall be taken as the maximum noise level. A3.5.3 Corresponding to the gear condition in c) of A3.2.1.1, the maximum value of the middle results of each gear when the engine speed exceeds the rated speed shall be taken as the maximum noise level:
A3.5.4 Corresponding to the conditions in A3.2.2.2.1, the middle result shall be taken as the maximum noise level. A3.5.5 Corresponding to the conditions in A3.2.2.2.2, the maximum value of the middle results of each speed condition shall be taken as the maximum noise level. A3.5.6 If the maximum noise level determined according to the above provisions exceeds the noise limit allowed for the vehicle model, the side corresponding to the result shall be re-measured four times, and the middle result of these four measurements shall be taken as the maximum noise level for the vehicle model. 43.5.7 The value of the maximum noise level shall be rounded to one decimal place according to the relevant provisions. A4 Measurement Record
Data on the technical parameters of the vehicle under test and the measuring instrument, the measuring conditions and the measuring results should be filled in the table in Appendix AB. Other matters that need to be explained in the measurement should be filled in the "Other Explanations" column. 126
AA1 Introduction
Appendix AA
Requirements for test pavement for noise measurement
GB 1495-2002
This appendix is ​​based on the main contents of ISO) 10844:1994 "Standard for the Acoustic Measurement of Road Vehicle Noise Test Pavement", and stipulates the technical requirements for the paving of the test pavement and the physical properties to be achieved and their measurement methods. 4A2 Terminology
This appendix uses the following terms.
AA2.1 Void ratio
Void ratio refers to the percentage of the pore volume between the aggregates in the pavement concrete to the total volume of the concrete, expressed as Vc. These pores are either connected to each other (closed pores) or connected to the surrounding atmosphere (open pores). The void ratio of the test pavement is determined by the following formula based on the core sample collected:
(1 pa/p)×100%
Where: P——apparent density of core sample t
——maximum theoretical density of core sample,
wherein the apparent density P is determined by the following formula: PA=m/V
Where: m——mass of core sample collected from test pavement, V is the volume of the core sample, excluding the air penetration volume of open gaps on the pavement surface. The density is determined based on the mass and volume of binder contained in each core sample, and the mass and volume of aggregate. Given by the following formula:
PR ​​VR+ VA
In the formula, M is the mass of the binder,
4A is the mass of the filler
the volume of the binder;
V.-the volume of the filler.
AA2.2 Sound absorption coefficient
The sound absorption coefficient refers to the ratio of the intensity of the incident sound waves absorbed by the pavement material to the intensity of the incident sound waves, expressed as: α=unreflected sound intensity/total incident sound intensity
Generally speaking, the sound absorption coefficient depends on the frequency and incident angle of the sound wave. The sound wave frequency range corresponding to the absorption coefficient specified in this standard is 400～1 ​​600 Hz+month vertical radiation,
AA2.3 Road surface structural depth
The road surface structural depth refers to the average depth of the open spaces on the road surface of a certain area, which is expressed as MTD (mm>: that is, the average thickness of a layer of very fine special specification glass ball sand required to fill the open spaces on the road surface, and the upper surface of this layer of ball sand is tangent to the plane of the road surface peaks.
AA3 Requirements for road surface characteristics
If the measured tread surface structural depth and the void ratio or sound absorption coefficient of the road surface meet the following requirements and also meet the design requirements of Article AA1.2, then the road surface is considered to meet the requirements of this appendix. 27
GB 1495--2002
AA43.1 Void ratio
The void ratio of the concrete of the test pavement after paving shall meet the requirement of Vc≤8. The measurement method is shown in AA5.1. AA3.2 Sound absorption coefficient
If the pavement does not meet the requirements of void ratio, its sound absorption coefficient must meet the requirement of α≤0.1. The measurement method is shown in AA3.5.2.
Note: Although road construction is more familiar with void ratio, the most relevant characteristic is the sound absorption coefficient. However, the sound absorption coefficient is only measured when the void ratio does not meet the requirements. Because the measurement of void ratio and related non-reflection have large uncertainties, it is possible to mistakenly deny some pavements based solely on the measurement of void ratio.
AA3.3 Road surface construction depth
The average road surface construction depth measured by the above-mentioned multiplication method shall meet the requirement of MTD=0.4mm. The measurement method is shown in AA3.5.3. A43.4 Uniformity of pavement
Ensure that the pavement surface in the test area is as uniform as possible in terms of its surface depth and voids. Note: It should be noted that if the rolling effect is different in some areas, the surface texture will be different and uneven. AA3.5 Inspection period
In order to check whether the pavement continues to meet the requirements for surface depth, voids or sound absorption coefficient specified in this Appendix, periodic pavement inspections shall be carried out at the following intervals: a) For voids or sound absorption coefficient
If the pavement is newly constructed, check once. If the new pavement meets the requirements, no further periodic inspections are required. If the new pavement does not meet the requirements, inspections may be carried out at a later time, because the voids in the pavement will be filled and compacted over time. b) For surface depth
If the pavement is newly constructed, check once. Check once when the noise test is started (note: it should be carried out 4 weeks after paving). Inspection shall be conducted once a year thereafter.
AA4 Design of test pavement
AA4.1 Area
The test site is shown in Figure A1. The shaded area shown in the figure is the smallest area paved and compacted by machinery using the specified material. When designing the test track, at least the area where the vehicle is driving during the test shall be paved with the specified pavement material and have the edges required for safe driving. The track width is required to be at least 3m, and the track length is extended by at least 10m at the AA and BB lines. AA4.2 Design and preparation of pavement
AA4.2.1 Basic design requirements
The test pavement shall meet the following four design requirements: AA4.2.1.1 Viscous green concrete shall be used. AA4.2.1.2 The maximum size of crushed stone shall be 8mm (the allowable range is 6.3~10mm). AA4.2.1.3 The thickness of the wearing layer shall be ≥30mm. AA4.2.1.4 The asphalt used for paving shall be unmodified asphalt of a certain grade of penetration. AA4.2.2 Assumption I Guidelines
Figure AA1 shows the gradation curves of gravel in asphalt mixtures. These curves will give the ideal characteristics as a guide for pavement builders. In addition, in order to obtain the ideal road surface structure and durability, some standard values ​​are given in Table AA1. The gradation curve is expressed as follows: P (%) (pass rate) -100 (d/dm) 1/2 Where: d is the square mesh size, mrl
dmr-8 mrm corresponds to the average curve,
d..x-[0 mm corresponds to the lower tolerance limit curve; 128
d=6. 3 mm corresponds to the upper tolerance limit curve. In addition to the above, the following requirements shall also be met: GB 1495-2002
The composition of sand (0.063mm<square mesh size<2mm) shall include no more than 55% natural sand and at least 45% of asphalt. a)
According to the highest road construction standards, the base and subbase shall ensure good stability and flatness; b)
The gravel shall be crushed (100% crushed surface) and shall be of high hardness; the gravel used in the mixture shall be clean; d
No additional gravel shall be added to the road surface. The penetration of asphalt (indicated by PEN) shall be 40-60.60-80, or even 80-100, depending on the local climatic conditions. If it is consistent with general practice, asphalt with lower penetration (higher hardness) shall be used as much as possible: u
T tttf t tttt
0. 0630.125
Figure AAT
Gravel quality, square sieve size (SM)>2mmSand quality, 0.063mmIf the test area outside the test track meets the requirements of air volume or sound absorption coefficient, it is not necessary to resurface it. AA7 Report on test road surface and noise test A47.1 Report on test road surface
AA7.1.1 Location of test track
A47.1.2 Type of track, density, type of gravel, maximum theoretical density (T) of concrete. Thickness of concreting layer and grading curve determined by taking core samples of test track.
AA7.1.3 Implementation method (type of rolling machine, weight of roller and number of rolling). AA1.4 Temperature of mixture during tread paving, ambient air temperature and wind speed. 130
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