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Following the ongoing software development, the continuously increasing accuracy of 0D/1D-simulation of combustion engines and chemical mechanisms for the use in reaction kinetic calculation open up a new possibility to calculate combustion processes. Particularly combustion processes with high dependency on reaction kinetics, such as knocking events, can be predicted. The simulation of knock events further allows a characterization of the knock behavior of LNG mixtures. This paper focuses on 1D-simulative investigation of knocking events to determine the Service Methane Number of different LNG mixtures and their dependency on single gas components. This is realized with two different approaches, which are presented in this work. In the first approach, measurement data and a Three-Pressure-Analysis-model are used to describe the in-cylinder condition at inlet valve closes.

The reduction of vehicle exhaust particle emissions is a success story of European legislation. Various particle number (PN) counters and calibration procedures serve as tools to enforce PN emission limits during vehicle type approval (VTA) or periodical technical inspection (PTI) of in-use vehicles. Although all devices and procedures apply to the same PN-metric, they were developed for different purposes, by different stakeholder groups and for different target costs and technical scopes. Furthermore, their calibration procedures were independently defined by different stakeholder communities. This frequently leads to comparability and interpretation issues. Systematic differences of stationary and mobile PN counters (PN-PEMS) are well-documented. New, low-cost PTI PN counters will aggravate this problem. Today, tools to directly compare different instruments are scarce.