噪音测试分原地噪音和行驶噪音
根据CNS 5799第六期机动车辆噪音管制标准值
https://i.imgur.com/JfL1R8t.jpg
汽车出厂加速噪音72~75分贝，原地噪音93~96分贝
机车出厂加速噪音73~77分贝，原地噪音81~92分贝
车辆出厂要测过才能挂牌
其他可以看这篇
#1YRW5yug
环保署的路检，噪音测试是原地噪音
空载的状态
https://i.imgur.com/SG6QZXz.jpg
引擎目标转速(最大转速50%或75%)
https://i.imgur.com/PWtfJNe.jpg
欧盟可以参考这篇
REGULATION (EU) No 540/2014 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL
of 16 April 2014
https://reurl.cc/8o9AYy
直接看重点
3.1.2
https://i.imgur.com/64wperF.jpg
The background noise (including any wind noise) shall be at least 10 dB
below the A-weighted noise pressure level produced by the vehicle under test.
背景噪音值需低于量测10dBA
4.2. Measurement of noise emitted by stationary vehicles
静止车辆噪音
4.2.5.2
https://i.imgur.com/d2jUDw0.jpg
the gear selector in the neutral position and the clutch engaged
空档测试
If the vehicle is fitted with a fan or fans having an automatic actuating
mechanism, this system shall not be interfered with during the sound level
measurements
车辆风扇不应干扰量测
The engine hood or compartment cover, if so fitted, shall be closed
引擎盖应关闭
4.2.5.3.2.1~3
https://i.imgur.com/fl66FUO.jpg
(1) 引擎转速条件(1/2, 3/4, 3750rpm)
(2) 与目标转速误差3%内，维持1秒
(3) 视为有效量测数据
4.2.6
https://i.imgur.com/DCs3hkw.jpg
At least three measurements for each test position shall be made.
至少量测3次
澳洲的NTC(National Transport Commission)
Noise Test Procedures for In-Service Motor Vehicles
https://reurl.cc/A73WWd
一样直接看重点
https://i.imgur.com/TZ4JLud.png
wind noise levels are at least 10dB(A) below the noise level being measured
风(背景)噪音应低于量测值10dBA
4.2.1
https://i.imgur.com/mqoFI28.jpg
The vehicle shall be stationary with the transmission in “neutral”
车辆静止且打空档
In the case of a motor cycle having no neutral gear position,
measurements shall be carried out with the rear wheel raised off the ground
没有N档，应把后轮抬起(无负载)
4.2.3
https://i.imgur.com/wDT8zLM.jpg
引擎转速(1/2或3/4)，若达不到则以引擎最大转速95%
4.2.5
https://i.imgur.com/GVBo9UY.jpg
The specified procedure shall be repeated until a least three consecutive
readings are obtained
至少三笔连续的读数
大部分国家地区噪音标准是跟随UN ECE R51：汽车噪音 (R41：机车噪音)
测试方法也都大同小异
排放或能耗测试，因为会上Dyno有负载，当然有配置大型工业风扇
但原地噪音测试
1. 空载测试条件哪来很多热量
2. 测试程序就要求尽量排除环境中的背景噪音值
一直说要风扇撞风真的满脸问号.....
※ 引述《HulkSmash (~灭世神浩克~)》之铭言：
: 刚刚看到一个影片是环保局验车
: 看之前的影片，应该是 BMW M3
: 然后就是原地踩油门，听车主说是6000转
: 而且还连续催5次，最后都冒烟了
: 先帮车主的引擎默哀10秒
: 好奇验个车，有需要连续催5次油门吗??
: 感觉验车的平常没开过，所以抓准时机
: 催到底，看能多大声的感觉 ??
: https://youtu.be/cnsxCh9XCSQ