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This study investigates the particle engine emission characteristics including particle-bound metals for different lubricants used in a direct injection (DI) engine fed with the hydrogen-rich reformate containing 75% mol. H2 and 25% mol. CO2. The particle number concentration, size distribution and content of trace metals in the emitted particles are measured, analyzed, and compared for the baseline gasoline-fed engine and the reformate-fed engine. The results show that for all tested lubricants the particle number and mass emission from the reformate-fueled engine are significantly higher than from the baseline gasoline-fed counterpart. Also, an ICP analysis performed on PM demonstrated that the content of trace elements from the lubricant are higher for the reformate fuel. This indicates that an excessive lubricant involvement in combustion is the reason of these findings.

Utilizing heat of exhaust gases for on-board alcohol reforming process (thermo-chemical recuperation - TCR) is a promising way of increasing the internal combustion engine (ICE) efficiency and emissions mitigation. Knowledge of the laminar burning velocity of alcohol reforming products is necessary for simulating performance of internal combustion engines with TCR and for in-depth studies of the combustion process. Laminar burning velocities of H2, CO, CO2 and CH4 mixtures that simulate methanol and ethanol steam reforming products for various water-alcohol ratios are investigated in this work. The influence of flame cellularity on burning velocity is studied as well. The burning velocity is measured experimentally using a spherical closed combustion vessel. Measurements are taken by a pressure measurement method during the pressure-rise period and prior to it by a high-speed Schlieren photography.

The paper presents an analytical two-dimensional model of two-phase turbulent jets with focus on fuel sprays in internal combustion engines. The developed model allows prediction of the fuel spray parameters including local fuel concentration and mixture velocity. The model proposed in this paper is based on the single-phase steady-state laminar axisymmetric jet flow field solution by Schlichting. This solution is amended to include transport of the discontinuous fuel phase in a stagnant air in the limit of a dilute fuel concentration. This two-phase jet flow model admits a closed form analytical solution for the fuel concentration distribution. This solution is then applied to turbulent jet flow as per the approach described by Schlichting and in other studies, and used to predict point-wise properties of fuel sprays in internal combustion engines. The results of model simulations are compared with the available experimental data.