Abstract Brake emissions generated from brake systems were investigated to elucidate the mechanism of airborne particle generation using commercial brake pads. Brake emission tests were performed using a 1/5 scale brake dynamometer enclosed in a chamber, and the particles were counted using an electrical low-pressure impactor (ELPI+) as a particle counter. The results revealed that the emission factor of low-steel brake pads was approximately five times greater than that of non-steel brake pads on average. In comparison, brake emissions in the number concentration were about two times greater in the case of using low-steel pads. Considerable amounts of off-brake emissions were also found after brake applications. Although multiple concentration peaks were observed in the particle size distribution, there was no correlation among chemical composition, size distribution, and particle morphology. On the other hand, the amount of brake emissions and the size distribution were strongly influenced by the pad surface topography, which comprised contact plateaus and lowlands, regardless of the type of pad.

中文翻译：

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全球统一轻型车辆测试程序 (WLTP) 期间刹车片磨损引起的颗粒排放分析

摘要 研究了制动系统产生的制动排放物，以阐明使用商用刹车片产生气载颗粒的机制。使用封闭在腔室中的 1/5 比例制动测功机进行制动排放测试，并使用电动低压冲击器 (ELPI+) 作为粒子计数器对粒子进行计数。结果表明，低钢刹车片的排放因子平均约为非钢刹车片的五倍。相比之下，在使用低钢垫的情况下，制动排放的数量浓度大约是其两倍。在制动应用后还发现了大量的离车排放物。虽然在粒度分布中观察到多个浓度峰，化学成分、粒度分布和颗粒形态之间没有相关性。另一方面，刹车排放量和尺寸分布受刹车片表面地形的强烈影响，包括接触高原和低地，而不管刹车片的类型。