Investigation with optical diagnostics of fuel/air interactions in GDI engine and influence of H2 addition for ignition enhancement of gasoline and NGV mixtures
20-month post-doctoral position at CORIA laboratory (September-2020)

The GDI with small cubic capacity strategy combined with technologies such as turbocharging and EGR2 are favoured by car manufacturers to reduce fuel consumption and achieve future targets in terms of polluting and CO2 emissions. While it is obvious that these strategies have high potentials for achieving the new high-level targets of future engines, they also open up new physical and technological questions, in particular linked to mixture ignition phase. During this post-doctoral work, several aspects of these ignition difficulties will be investigated in detail using advanced optical diagnostics applied in a single cylinder optical GDI engines. For this, two aspects will be particularly studied. The first will consist in evaluating the impact of the direct injection on the 3D flow organization in the engine at different crank angles. Indeed, previous studies in CORIA (Phd Lemétayer 2016, Daher 2018) have shown strong couplings between in-flow and direct gasoline injection. This post-doc project will focus on the impact of the injection on the turbulence properties at the spark plug position. Optical diagnostic as time resolved PIV and stereoscopic PIV will be used. In a second phase, the work will consist in a detailed study of the impact of H2 addition on the ignition processes. This study will rely on the joint use of a rapid compression machine (RCM – CERTAM Lab.) and an optical IDE engine bench (CORIA Lab.). It will consist in studying the initiation of combustion in poor and dilute doped mixtures of H2 under thermodynamic conditions close to those encountered in real engines.

The use of advanced optical diagnostics such as high-speed flame visualization, Particle Image Velocimetry (PIV) and Laser-Induced Fluorescence (LIF) will allow fine analysis of the initiation of combustion processes. These optical measurements will also be associated with more conventional combustion analyzes obtained from pressure cycles.

This work will be parts of two research programs managed by the CORIA laboratory (Vitamine3 and HyMAC4 Programs) in collaboration with CARNOT ESP and CERTAM institutes.

The 13th international conference series on Laser-light and Interactions with Particles (LIP2020)

Institute of Physics of the Polish Academy of Sciences, August 22-28th, 2020, Warsaw, Poland.

Date limite résumé: March 1st, 2020

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