Pilot analysis of tire tread characteristics and associated tire-wear particles in vehicles produced across distinct time periods.

Owing to stringent vehicle emission regulations and the shifting automotive landscape towards clean-energy vehicles, the emission of non-exhaust tire-wear particles and its implications for microplastic contamination have garnered substantial attention, emerging as a focal point of research interest. Unlike traditional source apportionment methods involving direct environmental sampling, this study focuses on the physical and chemical attributes of tire treads, the tread temperature changes, and the tire-wear particle emissions of three light-duty vehicles manufactured between 2011 and 2021. This study advances the understanding of the effects of tire properties on particle emissions, which provides preliminary information on low-wear tires.

Parallel perturbation analysis of combustion cycle-to-cycle variations and emissions characteristics in a natural gas spark ignition engine with comparison to consecutive cycle method.

Severe combustion cycle-to-cycle variations (CCVs) in spark ignition (SI) engines significantly increase partial or incomplete combustion cycles, which may result in combustion instability or even misfire under extreme conditions, thereby seriously affecting the engine performance and increasing the unburned hydrocarbon and carbon monoxide emissions. In this study, the consecutive cycle method (CCM) and parallel perturbation method (PPM) are utilized to simulate the CCVs in a natural-gas (NG) SI engine. Specifically, 25 consecutive and concurrent cycles of the SI engine are simulated, and simulation results are compared with the experimental data.