轻型车辆固定排气系统噪音等级,引擎速度测量方式

[中文适用范围]： 本SAE推荐实践建立了用于测量乘用车、多用途车辆和轻型卡车在静止条件下的外部排气声级的测试程序、环境和仪器，提供了一系列发动机转速下排气系统声级的连续测量。 本文件仅适用于配备内燃机的道路车辆。 该方法旨在满足简单性的要求，只要它们与车辆操作条件下的结果再现性一致。 本文件的范围内包括测量静止A加权声压级，适用于： • 制造阶段的测量 • 官方测试站的测量 • 路边测试的测量 它既没有规定在发动机以实际负载运行时检查排气声压级的方法，也没有规定检查排气声压级是否符合道路车辆类别的一般噪声限值的方法。它提供了检测排气系统共振的方法，这些共振可能影响外部和内部声音质量。 SAE J2805提供了评估车辆噪声排放的方法，与实际车辆负载和速度下的车辆噪声排放一致。 本文件包含了ISO 5130:2019的某些规定，用于测量排气系统的声级（见附录A）。 [外文原描述]： This SAE Recommended Practice establishes the test procedure, environment, and instrumentation to be used for measuring the exterior exhaust sound level for passenger cars, multipurpose vehicles, and light trucks under stationary conditions providing a continuous measure of exhaust system or simulated exhaust sound level over a range of engine speeds or simulated engine speeds.This document applies only to road vehicles equipped with an internal combustion engine or with an external sound system.The method is designed to meet the requirements of simplicity as far as they are consistent with reproducibility of results under the operating conditions of the vehicle.It is within the scope of this document to measure the stationary A-weighted sound pressure level during:Measurements at the manufacturing stageMeasurements at official testing stationsMeasurements at roadside testingIt does neither specify a method to check the exhaust sound pressure level when the engine is operated at realistic load nor a method to check the exhaust sound pressure levels against a general noise limit for categories of road vehicles. It provides the means for detecting exhaust system resonances with the potential to affect both exterior and interior sound quality.SAE J2805 provides methods to assess vehicle noise emission consistent with in-use vehicle noise emissions at realistic vehicle loads and speeds.This document incorporates certain provisions of ISO 5130:2019 for measuring the sound level of exhaust systems (see Appendix A).