JSAE 20199152 SAE 2019-YY-YYYY Measurement of Sub-23 nm particles emitted by gasoline direct injection engine with new advanced instrumentation Stéphane Zinola, Mickaël Leblanc, Loïc Rouleau, Xavier Dunand IFP Energies nouvelles, Institut Carnot IFPEN TE, France Penelope Baltzopoulou, Leonidas Chasapidis, Daniil Deloglou, Anastasios D. Melas Athanasios G. Konstandopoulos, Aerosol & Particle Technology Laboratory (APTL), CPERI/CERTH & Department of Chemical Engineering, Aristotle University Thessaloniki, Greece Tobias Rüggeberg, Martin Fierz, Heinz Burtscher Fachhochschule Nordwestschweiz (FHNW), Switzerland Alberto Tejero, Mario Amo, Daoíz Zamora Sociedad Europea de Análisis Diferencial de Movilidad SL (SEADM), Spain Copyright © 2019 SAE Japan and Copyright © 2019 SAE International ABSTRACT The research on health effects of soot particles has demonstrated their toxic impact on humans, especially for the smallest ones that can pass through the lungs into the bloodstream and be transferred to other parts of the body. Since the Euro 5b regulation, the total particle number (PN) at the exhaust is limited, but the associated protocol developed by the Particle Measurement Program (PMP) group defined a counting efficiency at the 23 nm cut-off particle diameter to avoid measurement artefacts [1][2]. Recent studies have demonstrated that the last generation Euro 6 engines can emit as many particles in the range 10 – 23 nm as beyond 23 nm [3]. The SUREAL-23 project (Understanding, Measuring and Regulating Sub-23 nm Particle Emissions from Direct Injection Engines Including Real Driving Conditions), funded by Horizon 2020 EU-program, aims to develop sampling, conditioning and measuring instruments and associated methodologies to extend the existing protocol down to at least 10 nm. This measurement setup was evaluated on various light duty direct injection platforms. This communication focuses on a gasoline-DI vehicle with a Euro 6b engine. Tests were conducted on multiple operating conditions (moderate and aggressive driving cycles, hot and cold starts, and several fuel and lubricant formulations). Sampling and conditioning were done with a two-stage dilution system, with a built-in catalytic stripper. The prototype instruments have been compared to commercial reference soot particle analyzers (TSI CPC, Horiba MEXA-2000 SPCS and Cambustion DMS500). A good consistency between all the measurements was demonstrated, with a satisfactory repeatability and robustness of the proposed measurement setup and of the associated methodology. An on-board version of the proposed setup is currently being developed to allow PN measurement in Real Driving Emissions (RDE) conditions. INTRODUCTION A large fraction of the total number of particles emitted by direct injection engines are below the adopted 23 nm diameter threshold [3] and although the EU aims to regulate these emissions and impose limits for new light-duty vehicles, this is not yet possible due to the absence of accurate and reliable quantification methods, especially under real driving conditions. The main reason for this is the lack of adequate knowledge regarding the nature of sub-23 nm particles from different engine/fuel combinations under different engine operating. The EU-funded project SUREAL-23 aims to overcome such barriers by introducing novel technologies for the measurement of sub-23 nm exhaust particle concentration, size and composition. The objectives of the present work are to evaluate the novel sampling and dilution system, and the advanced particle measurement technologies that were developed in the framework of the project. The