This standard applies to the measurement of noise from various types of motor vehicles on the road when they are stationary. Stationary means that the vehicle is not moving and the engine is in an idling state. The measurement data obtained by the method specified in this standard can be used to evaluate and check the main noise sources of motor vehicles - exhaust noise and engine noise levels. The data directly measured by this method cannot represent the maximum noise level of the vehicle. GB/T 14365-1993 Acoustics Motor Vehicle Stationary Noise Measurement Method GB/T14365-1993 Standard Download Decompression Password: www.bzxz.net
This standard applies to the measurement of noise from various types of motor vehicles on the road when they are stationary. Stationary means that the vehicle is not moving and the engine is in an idling state. The measurement data obtained by the method specified in this standard can be used to evaluate and check the main noise sources of motor vehicles - exhaust noise and engine noise levels. The data directly measured by this method cannot represent the maximum noise level of the vehicle.
Some standard content:
National Standards Museum of the People's Republic of China Acoustics--Measurement of noise emltted by stationary road vehicles GB/T14365-93 This standard adopts the international standard ISO5130-1982-Measurement of noise radiated by stationary road vehicles--Simplified method". 1 Subject content and applicable scope This standard applies to the measurement of noise of various types of motor vehicles traveling on the road under fixed load. Fixed load means that the vehicle is not traveling and the engine is in a state of full load operation. The measurement data obtained by the method specified in this standard can be used to evaluate and check the main noise sources of motor vehicles - exhaust noise and engine noise levels. The data directly measured by this method cannot represent the maximum noise level of the vehicle during driving. 2 Reference standard GB3785-83 Electrical and acoustic performance and test methods of acoustic meters" 3 Measurement environment 3.1 Measurement site 3.1.1 The measurement site should be an open, flat ground made of hard materials such as concrete and asphalt. Its edge should be at least 3m away from the outer contour of the vehicle (see Figure 1 and Figure 2). Large obstacles outside the measurement site, such as parked vehicles, buildings, billboards, trees, parallel walls, etc., must be at least 3 meters away from the microphone. m. 3.1.2 Except for the measurement personnel and the driver, no other personnel shall be present at the measurement site. 3.2 Background noise 3.2.1 During the measurement, the background noise at the microphone position (including the influence of wind) should be at least 10dB(A) lower than the noise being measured. The background noise of this standard refers to noise outside the vehicle. 3.2.2 If the background noise is 6 to 10dB(A) lower than the measurement noise, the correction value in Table 1+ should be subtracted from the measurement result. If the difference is less than 6dB(A), the measurement is invalid. Measurement noise and background noise values||tt ||3-3 Wind speed Table 1 Background noise correction value 3.3.1 When the wind speed exceeds 2m/s, the sound level meter should use a windshield, and pay attention to the impact of gusts on the measurement. 3.3.2 When the wind speed during measurement is greater than 5m/s, the measurement is invalid. 4 Measuring instrumentswwW.bzxz.Net 4.1 Noise measuring instruments 4.1.1 Sound level meters or other measuring systems equivalent to sound level meters should comply with the requirements for [type or [type only] instruments in (GK3785. Approved by the State Administration of Technical Supervision on March 17, 1993 and implemented from December 1, 1993 to December 1, 2001 : com4. 1.2 Measurement using A-weighted sound level meter, fast gear CB/T 14365-93 4.1.3 Before and after measurement, the instrument should be calibrated as required, the difference between the two calibration values should not exceed 1dB, and the accuracy of the calibrator should be better than or equal to ±0.5 dB. 4.2 Instrument for measuring engine speed The accuracy of the engine tachometer should be better than 3%. 5 Measurement procedure 5.1 Vehicle position and status 5.1.1 The vehicle is located in the center of the measurement site, the transmission is in neutral, the handbrake is tightened, and the clutch is engaged. For motorcycles without neutral position, the rear wheel should be suspended. 5.1.2 The engine accumulator, windows and doors should be closed, and the vehicle's air conditioner and other auxiliary equipment should be turned off. 5.1.3 During measurement, the engine outlet water temperature and oil temperature should comply with the manufacturer's regulations. 5.2 Number of measurements The test is repeated at each measuring point of each type of test until three consecutive readings have a variation range within 2 dB, and the arithmetic mean is taken as the measurement result. 5.3 Exhaust noise measurement (see Figure 1) 5.3.1 Microphone position 5-3.1.1 The microphone is equidistant from the exhaust port end and in any case shall not be less than 0.2 m from the ground. 5.3.1.2 The reference axis of the microphone shall be parallel to the ground and shall form an angle of 45°±10° with the plane passing through the exhaust port airflow direction and perpendicular to the ground. The microphone faces the exhaust port. It is 0.5 m away from the exhaust port end and placed on the outside of the vehicle. 5.3.1.3 When the vehicle is equipped with two or more exhaust pipes, and the interval between the exhaust pipes is not more than 0.3 rm, and connected to a muffler, only one measurement position is required. The microphone shall be selected on the exhaust arm located closest to the outside of the vehicle. If two or more exhaust pipes are on a straight line perpendicular to the ground at the same time, the exhaust pipe that is highest from the ground shall be selected. 5.3.1.4 For vehicles equipped with multiple exhaust pipes and the interval between each exhaust pipe is greater than 0.3 m, each exhaust pipe shall be measured and the highest sound level shall be recorded. 5.3.1.5 For vehicles with vertical exhaust pipes, the microphone shall be placed at the same height as the exhaust pipe outlet, with the microphone facing upward and its reference axis perpendicular to the ground. The microphone shall be placed on the side of the vehicle that is closer to the exhaust pipe and 0.5 m away from the exhaust outlet. 5.3.1.6 If the vehicle cannot meet the requirements of 5.3.1.1 and 5.3.1.2 due to design reasons (such as spare tire, fuel tank, battery, etc.), a measurement point diagram shall be drawn and the position of the microphone shall be marked. The microphone shall face the exhaust outlet and be placed in a place that meets the above conditions as much as possible and is greater than 0.2 m away from the nearest obstacle. 5.3.2 Engine running conditions 5.3.2.1 Engine speed measurement: For gasoline engine vehicles (except motorcycles), take ±50 r/min; for diesel engine vehicles (except motorcycles), take ±50 r/min; for motorcycles, when mt>5 000 r/min, take ±50 1/min; when mt<5000 r/min, take ±50 r/min, - refers to the rated speed specified by the manufacturer. 5.3.2.2 During measurement, after the engine stabilizes at the above speed, measure the noise during the process of decelerating from the stable speed as quickly as possible, and then record the highest sound level. 5.4 Engine noise measurement (see Figure 2) 5.4.1 Microphone placement 5.4.1.1 The microphone is placed 0.5m above the ground and facing the vehicle, on the side of the vehicle without the driver's seat. 0.5m from the vehicle's profile, the microphone reference axis is halfway above the ground, in a vertical plane whose position depends on the position of the engine. Front engine; the vertical plane passes through the front axle. Rear engine; the vertical plane passes through the rear axle. GB/T14365—93 Mid-mounted engine and motorcycle: vertical plane passes through the midpoint of the front and rear wheelbase, exhaust pipe center height +name " Exhaust pipe center height Exhaust pipe in the warning 1 Exhaust noise measurement site and microphone position Left||||Mid-mounted engine ?Rear engine GB/T14365—93 Right Figure 2 Engine noise measurement site and microphone position Unit, m Three-wheeled vehicle and three-wheeled motorcycle 5.4.1.2 Two-wheeled motorcycle, the microphone is placed on the right side of the vehicle's forward direction. For two-wheeled motorcycle, the microphone is placed on the left side of the vehicle's forward direction, the microphone faces the vehicle, and is 0.5 meters away from the outside of the vehicle. r, 0.5 m above the ground. 5.4.2 Engine operating conditions During the measurement, the engine shall be accelerated from idling speed to the speed specified in 5.3.2 as quickly as possible and maintained for the necessary time with an appropriate device. Measure the noise during the acceleration from idling speed to steady speed, and then record the highest sound level. 6 Data processing Fill in the measurement data according to the record form Vehicle unit Vehicle license plate number Vehicle model Engine model Rated power, kW Rated speed, r/min Measured speed, r/min Model of measuring instrument Number of measurements Sound level L Number of measurements Strict Level L Remarks, Add explanation; GB/T14365-93 Motor vehicle noise measurement record Single location Land condition Wind speed m/s Background noise, RCA Background noise correction value. dB(A) Irregular measurement point diagram Exhaust noise measurement results Engine noise measurement results Measurement unit: Measurement personnel: This standard is proposed by the National Industry-University Standardization Technical Committee: This standard is under the responsibility of Beijing Labor Protection Institute, and the Ministry of Communications Highway Materials Research Institute participated in the preparation of the Institute of Automobile Research. dB(A) Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.