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Light-duty China-6, which is among the most stringent vehicle exhaust emission standards globally, mandates the monitoring and reporting of real driving emissions (RDE) from July, 2023. In the process of regulation promulgation and verification, more than 300 RDE tests have been performed on over 50 China-5 and China-6 certified models. This technical paper endeavors to summarize the experience of RDE practice in China, and discuss the impacts of some boundary conditions (including vehicle dynamic parameters, data processing methods, hybrid propulsion and testing altitude) on the result of RDE measurement. In general, gasoline passenger cars confront few challenges to meet the upcoming RDE NOx requirement, but some China-5 certified samples, even powered by naturally-aspirated engines may have PN issues. PN emissions from some GDI-hybrid powertrain systems also need further reduction to meet China-6 RDE requirements.

With the increasing of people's demand for comfort of vehicles, the noise generated by the reverse of windshield wiper causes wide attention. In this paper, as the front windshield wiper of one car is considered, the impacts of the preload of wiper lever spring, the torsional stiffness of blade neck and the flexible connection between the wiper arm and the wiper lever on the vibration excitation applied to the front windshield are analyzed based on the multi-body dynamic model of wiper system. The dynamic model includes the crank pivot, the four linkage mechanism, the wiper blades, the wiper arms and the windscreen glass which has been established considering with elastic contact between the wiper blade and the front windshield. Based on the analysis results the dimensions of cross-section of the wiper blade rubber and the flexible connection between the wiper arm and the wiper lever are designed to reduce the quick-return impact of wiper lever.

Wiper noise generated in the wiping process is one of the main influence factors affecting the driving comfort. Since the dynamic contact pressure of the contact between a blade and a windshield glass is difficult to be measured, it is also difficult to predict the degree of the wiper noise. In this paper, in the view of the reversal noise problem of a passenger-vehicle windscreen wiper system, the system dynamic models of the both wipers on the sides of the driver and copilot were built as considering the blade deformation and the elastic contact between the blades and the windscreen glass, including the crank pivot, the four linkage mechanism, the wiper blades, the wiper arms and the windscreen glass. The motion of the wiper system and the pressure distributions between the blades and the windscreen glass were analyzed under the half-dry condition.