GB/T 44040-2024 Measurement methods for noise emitted by heavy-duty vehicles in multiple driving mode conditions
1 Scope
This document specifies the terms and definitions, measuring instruments, measuring conditions, measurement requirements and methods for measuring noise emitted by heavy-duty vehicles in multiple driving mode conditions.
This document is applicable to the measurement of noise emitted by Categories M3, N2, and N3 vehicles, as well as Category M2 vehicles with a maximum total mass greater than 3,500kg in multiple driving mode conditions.
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 3730.1 Terms and definitions of motor vehicles, trailers and combination vehicle - Part 1: Types
GB/T 3730.2 Road vehicle - Masses - Vocabulary and codes
GB/T 12534 Motor vehicles - General rules of road test method
GB/T 15089 Classification of power-driven vehicles and trailers
GB/T 15173 Electroacoustics - Sound calibrators
GB/T 19596 Terminology of electric vehicles
GB/T 22157 Acoustics - Specification of test tracks for measuring noise emitted by road vehicles and their tyres
GB/T 38146.2 China automotive test cycle - Part 2: Heavy-duty commercial vehicles
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 3730.1, GB/T 3730.2, GB/T 15089, GB/T 19596 and GB/T 38146.2 as well as the following ones apply.
3.1
test mass
mt
mass of different types of test vehicles used for noise testing after being loaded according to different load conditions
Note: The unit is kilograms (kg).
3.2
total power of vehicle
Pn
total power of all power sources directly involved in driving the vehicle
Note 1: The unit is kilowatts (kW).
Note 2: The total power of vehicles using fuel engines refers to the maximum net power of engines measured according to GB/T 17692. For battery electric vehicles, it refers to the sum of the peak power of all drive motors measured according to GB/T 18488.2. For hybrid electric vehicles, it refers to the sum of the maximum net power of the engine measured according to GB/T 17692 and the peak power of the drive motor(s) measured according to GB/T 18488.2. For fuel cell vehicles, it refers to the peak power of the drive motor(s) measured according to GB/T 24554.
3.3
engine speed at maximum net power
S
speed of engine when it outputs the maximum net power, as specified in GB/T 17692
Note 1: The unit is revolutions per minute (r/min).
Note 2: If the maximum net power can be achieved at multiple engine speeds, the highest speed corresponding to the maximum net power is considered the engine speed at maximum net power.
3.4
reference point
locating point used to represent the position of a test vehicle during noise measurements
Note 1: For test vehicles with a front-mounted engine (or drive motor), the reference point is the foremost point of the test vehicle. For test vehicles with a mid-mounted or rear-mounted engine (or drive motor), the reference point is the edge of the engine (or drive motor) closest to the forward driving direction of the test vehicle.
Note 2: For test vehicles with multiple drive motors, if the main drive motor or the forward-positioned drive motor (in cases where multiple drive motors have equal power) is front-mounted, the reference point is the foremost point of the test vehicle. If the main drive motor or the forward-positioned drive motor is mid-mounted or rear-mounted, the reference point is the edge of the main or forward-positioned drive motor closest to the forward driving direction of the test vehicle.
4 Measuring instrument
4.1 Acoustic measuring instrument
The sound level meters or other equivalent measuring systems used for measurement shall meet the requirements for Level 1 sound level meters as specified in GB/T 3785.1 (windscreen shall be included, if applicable). During measurement, the "F" time-weighting characteristic and "A" frequency-weighting characteristic of sound level meter shall be used. If a sound level meter or measuring system capable of automatically capturing "A"-weighted sound pressure levels is used, the reading time interval shall not exceed 30ms.
4.2 Calibration of acoustic measuring instrument
Before and after the measurement, the acoustic measuring instrument shall be calibrated using a Level 1 acoustic calibrator compliant with GB/T 15173. Without making any further adjustments, if the difference between the post-test calibration reading and the pre-test calibration reading exceeds 0.5dB(A), the measurement results obtained after the pre-test calibration shall be considered invalid.
4.3 Other measuring instruments
The measuring instruments shall include the following equipment, with accuracies meeting the following requirements:
a) Tachometer: ±2%;
b) Vehicle speed measuring instrument: ±0.5%;
c) Thermometer: ±1℃;
d) Anemometer: ±1.0m/s;
e) Barometer: ±0.5kPa;
f) Relative humidity meter: ±5%;
g) Tyre gauge: ±10kPa.
Contents 1 Scope 2 Normative references 3 Terms and definitions 4 Measuring instrument 5 Measuring conditions 6 Measurement requirements and methods Annex A (Informative) Record form for measurement of noise emitted by heavy-duty vehicles in multiple driving mode conditions Bibliography
GB/T 3730.1、GB/T 3730.2、GB/T 15089、GB/T 19596、GB/T 38146.2界定的以及下列术语和定义适用于本文件。 3.1 测试质量 test mass mt 不同种类试验车辆根据不同载荷条件加载后，用于噪声测试时的质量。 注：单位为千克(kg)。 3.2 汽车总功率 total power of vehicle Pn 汽车直接参与驱动的动力源功率总和。 注1:单位为千瓦(kW)。 注2:使用燃料发动机的汽车总功率是指根据GB/T 17692测得的发动机最大净功率；纯电动汽车总功率是指根据GB/T 18488.2测得的所有驱动电机峰值功率之和；混合动力汽车总功率是指根据GB/T 17692测得的发动机最大净功率与根据GB/T 18488.2测得的驱动电机峰值功率之和；燃料电池汽车总功率是指根据GB/T 24554测得的驱动电机峰值功率。 3.3 发动机最大净功率转速 engine speed at maximum net power S 根据GB/T 17692规定发动机输出最大净功率时对应的转速。 注1: 单位为转每分(r/min)。 注2: 如发动机在不同转速均得到最大净功率，则发动机最大净功率对应的最高转速为最大净功率转速。 3.4 参考点 reference point 试验车辆进行噪声测量时用于代表车辆位置的定位点。 注1:对于发动机(驱动电机)前置试验车辆，参考点为试验车辆最前端点；发动机(驱动电机)中置、后置试验车辆，参考点为发动机(驱动电机)靠近试验车辆行驶方向前端的边缘。 注2:对于有多个驱动电机试验车辆，主驱动电机或靠前驱动电机(多个驱动电机功率相等)前置时，参考点为试验车辆最前端点；主驱动电机或靠前驱动电机(多个驱动电机功率相等)中置、后置时，参考点为主驱动电机或靠前驱动电机靠近试验车辆行驶方向前端的边缘。
4 测量仪器
4.1 声学测量仪器 测量用声级计或其他等效的测量系统应满足GB/T 3785.1规定的1级声级计的要求(如果适用，还应包括防风罩)。测量时，应使用声级计的“F”时间计权特性和“A”频率计权特性。当使用能自动采集测量“A”计权声压级的声级计或测量系统时，其读数时间间隔不应超过30ms。 4.2 声学测量仪器校准 测量前后，应用符合GB/T 15173规定的1级声校准器对声学测量仪器进行校准。在没有再做任何调整的条件下，如果后一次校准读数相对前一次校准读数的差值超过0.5 dB(A),则判定前一次校准后的测量结果无效。 4.3 其他测量仪器 测量仪器应包括如下设备，准确度应满足下列要求： a) 转速测量仪器，±2%; b) 车速测量仪器，±0.5%; c) 温度计，±1℃; d) 风速仪，±1.0m/s; e) 大气压计，±0.5kPa; f) 相对湿度计，±5%; g) 轮胎气压表，±10kPa。
