2015-today: R&D Engineer IFP Energies nouvelles - Mobility & Systems Division - Energy & Emissions Conversion Department
2003-2014: R&D Engineer IFP Energies nouvelles & Projet manager - Catalysis & Separation Division: Divided Engineering Department
1993-2003: R&D Engineer IFP Energies nouvelles - Process Engineering Division: Catalytic Engineering Department
EDUCATION
2014-2015: IFP-School (France) - Powertrain and Energy - Master degree
1989-1992: University of Lyon (France) - Catalysis - PhD
1986-1989: University of Nantes (France) - Materials - Master degree
RESEARCH, TEACHING, or OTHER INTERESTS
Automotive Engineering, Inorganic Chemistry, Chemical Engineering, Catalysis
62
Scopus Publications
Scopus Publications
A comprehensive study for the identification of the requirements for an optimal H2 combustion engine Olivier Laget, Loïc Rouleau, Matthieu Cordier, Florence Duffour, Giampaolo Maio, Vincent Giuffrida, Rajesh Kumar, Ludovic Nowak International Journal of Engine Research, 2023 As part of the fight against global warming and to achieve greenhouse gas emission targets, it is crucial to reduce the carbon footprint of ground transportation. Mobility needs are continuously growing with increase in population. All these factors will lead to an upsurge in the energy demand for the mobility in the very next future. Consequently, the diversification of low carbon energy sources is urgently required. Hydrogen can be used for mobility solution in its two energy conversion mechanisms: The Fuel Cell technology or the Internal Combustion Engine (ICE). The latter option, studied in the present work, offers the advantages of current fossil fuel engines – existing and proven technology, lifetime, controlled cost – with a very low carbon footprint. The overall objective of the study is to define the specifications of a dedicated Hydrogen direct injection combustion system for ground transportation application with the best fuel efficiency and lower raw emissions, to minimize the aftertreatment needs. A complete experimental and numerical study was carried out to get valuable information on various phenomena occurring throughout the engine cycle. The very first step of the study consisted in performing experimental investigations. For this purpose, an all metal single cylinder engine originally designed for gasoline spark ignited combustion (tumble air motion, gasoline direct injection) was modified for hydrogen direct injection combustion. The gas-gas injection was experimentally studied in the High Pressure/High Temperature vessel available at IFPEN. Those experiments were used to calibrate the 3D CFD numerical approach. Based on a 0D pre-study (boundary conditions) and using the injection modeling calibration introduced before, 3D CFD simulations have been then carried out with specific hydrogen kinetics properties. Finally, this comprehensive study highlights the specificities of ICE running with hydrogen. It provides indications and guidelines for further developments and optimization of hydrogen combustion engines.
Assessment of Dilution Options on a Hydrogen Internal Combustion Engine Loic Rouleau, Ludovic Nowak, Florence Duffour, Bruno Walter SAE Technical Papers, 2023 <div class="section abstract"><div class="htmlview paragraph">The hydrogen internal combustion engine is a promising alternative to fossil fuel-based engines, which, in a short time, can reduce the carbon footprint of the ground transport sector. However, the high heat release rates associated with hydrogen combustion results in higher NOx emissions. The NOx production can be mitigated by diluting the in-cylinder mixture with air, Exhaust Gas Recirculation (EGR) or water injected in the intake manifold. This study aims at assessing these dilution options on the emissions, efficiency, combustion performance and boosting effort. These dilution modes are, at first, compared on a single cylinder engine (SCE) with direct injection of hydrogen in steady state conditions. Air and EGR dilutions are then evaluated on a corresponding 4-cylinder engine by 0D simulation on a complete map under NOx emission constraint.</div><div class="htmlview paragraph">On the SCE at 3000rpm and 10.7bar IMEP, air and EGR dilutions allow a high dilution rate, leading to a significant NOx reduction: from 2.8g/kWh to less than 0.05g/kWh. The indicated efficiency goes through a maximum of about 45.5% with NOx emissions around 0.4g/kWh without affecting the lubricant consumption, calculated from carbon-bearing gas emissions. The water injection doesn’t affect the efficiency but reduces NOx emissions moderately without inducing excessive lubricant consumption. For the three dilution options, a common guide curve of NOx emissions versus a thermal dilution rate, based on the fuel chemical energy, diluent heat capacity and water vaporization latent heat, is presented. The best indicated efficiency for a tolerable NOx level of 0.4g/kWh is achieved for lambda of 2.4 with air dilution path and EGR rate of 10% at lambda of 2. After these dilution tests involving hydrogen and possibly high content of water in the chamber, only a thin layer of corrosion is observed on the iron cast liner without any structural or mechanical damage. The 0D simulation shows the interesting combination of air and EGR dilution allowing higher load under NOx emission constraint. EGR gases containing water with high heat capacity allows to reduce the quantity of diluent at high load, therefore the filling work and turbocharger effort.</div></div>
A comprehensive study for the identification of the requirements for an optimal H2 combustion engine Comodia 2022 10th International Conference on Modeling and Diagnostics for Advanced Engine Systems, 2022
Experimental and Numerical Investigation on Hydrogen Internal Combustion Engine Loic Rouleau, Florence Duffour, Bruno Walter, Rajesh Kumar, Ludovic Nowak SAE Technical Papers, 2021 <div class="section abstract"><div class="htmlview paragraph">Hydrogen may be used to feed a fuel cell or directly an internal combustion engine as an alternative to current fossil fuels. The latter option offers the advantages of already existing hydrocarbon fuel engines - autonomy, pre-existing and proven technology, lifetime, controlled cost, existing industrial tools and short time to market - with a very low carbon footprint and high tolerance to low purity hydrogen. Hydrogen is expected to be relevant for light and heavy duty applications as well as for off road applications, but currently most of research focus on small engine and especially spark ignition engine which is easily adaptable. This guided us to select modern high-efficient gasoline-based engines to start the investigation of hydrogen internal combustion engine development.</div><div class="htmlview paragraph">This study aims to access the properties and limitations of hydrogen combustion on a high-efficiency spark ignited single cylinder engine with the support of the 3D-CFD computation.</div><div class="htmlview paragraph">A high efficiency gasoline single cylinder engine was adapted for hydrogen combustion system with a direct injection and a platinum-free cold spark plug. The injection and camshaft phasing ranges were defined to limit the passage of hydrogen in the intake and exhaust manifolds. The experiments were focused on two operating points (2000rpm and 3000rpm at IMEP=10 bar) at various fuel-air equivalent ratios, fuel injection and air intake camshaft timings and in-cylinder charge motion, at high compression ratio (CR=14). 3D-CFD computation was carried out on CONVERGE<sup>TM</sup> to visualize and understand the local mixing in the combustion chamber.</div><div class="htmlview paragraph">The study revealed that the highest indicated efficiency (close to 47%) coupled with low NO<sub>X</sub> and acceptable unburnt H<sub>2</sub> emissions (respectively below 0.5g/kWh and 1% input energy) was obtained at lean mixture, early hydrogen injection and high tumble level. The pre-ignition known as one of the highest challenges in hydrogen combustion is successfully limited by adjusting the injection timing and camshaft phasing. 3D-CFD simulations showed that optimum fuel injection and intake camshaft timings should favor the homogenization of the mixture and avoid the presence of rich zones near hot spots to avoid pre-ignition.</div></div>
Measurement of Sub-23 nm particles emitted by gasoline direct injection engine with new advanced instrumentation Stéphane Zinola, Mickaël Leblanc, Loïc Rouleau, Xavier Dunand, Penelope Baltzopoulou, Leonidas Chasapidis, Daniil Deloglou, Anastasios D. Melas, Athanasios G. Konstandopoulos, Tobias Rüggeberg, Martin Fierz, Heinz Burtscher, Alberto Tejero, Mario Amo, Daoíz Zamora SAE Technical Papers, 2019 <div class="section abstract"><div class="htmlview paragraph">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 [<span class="xref">1</span>][<span class="xref">2</span>]. 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 [<span class="xref">3</span>].</div><div class="htmlview paragraph">The SUREAL-23 project (Understanding, Measuring and Regulating <u>Su</u>b-<u>23</u> nm Particle Emissions from Direct Injection Engines Including <u>Real</u> 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.</div><div class="htmlview paragraph">An on-board version of the proposed setup is currently being developed to allow PN measurement in Real Driving Emissions (RDE) conditions.</div></div>
Experimental and Numerical Analysis of Diluted Combustion in a Direct Injection CNG Engine Featuring Post- Euro-VI Fuel Consumption Targets Mirko Baratta, Daniela Misul, Prashant Goel, Danilo Laurenzano, Betrand Lecointe, Loic Rouleau, Frederic Ravet, Panagiotis Christou SAE Technical Papers, 2018 — In recent years, the progress in both hardware and software enabled user-space applications to capture packets at 10Gbit/s line rate. However, processing packets at such rates with software running on Commercial Off-The-Shelf (COTS) hardware is still far from being trivial. In the literature, this challenge has been extensively studied for Network Intrusion Detection Systems (NIDS), where operations are per-packet and easier to parallelize also thanks to hardware acceleration. Conversely, the scalability of Statistical Traffic Analyzers (STA) is intrinsically more complex as it implies tracking per-flow state to collect statistics. This challenge received less attention so far, and it is the focus of this work. We discuss the design choices to enable a STA to collects hundreds of per-flow metrics at a multi 10Gbit/s line rate. We leverage a handful of hardware advancements proposed over the last years (e.g., RSS queues, NUMA architecture), and we provide insights on the trade-offs they imply when combined with state of the art packet capture libraries and multi-process paradigm. We outline the principles to achieve an optimized STA, and we apply them to engineer DPDKStat, a solution combining the Intel DPDK framework with the traffic analyzer Tstat. Using traces collected from real networks, we demonstrate that DPDKStat achieves 40Gbit/s of aggregated rate with a single COTS PC.
Potential of templated mesoporous aluminas as supports for HDS CoMo catalysts Andres Miño, Christine Lancelot, Pascal Blanchard, Carole Lamonier, Loïc Rouleau, Magalie Roy-Auberger, Sébastien Royer, Edmond Payen New Journal of Chemistry, 2016 Activities in thiophene hydrodesulfurization were increased by a factor three when using aluminas, as support for CoMo catalysts, prepared using an optimized sol–gel method.
Revisiting the side crushing test using the three-point bending test for the strength measurement of catalyst supports D. Staub, S. Meille, V. Le Corre, J. Chevalier, L. Rouleau Oil and Gas Science and Technology, 2015 The side crushing test is commonly used to characterize the mechanical strength of catalyst supports. However its interpretation is complex for cylindrical supports due to their irregular geometry and the various fracture modes induced. A better analysis of the crushing test, altogether with a comparison of the results obtained with the three-Point Bending test (3PB) and an analysis of the defects present within the supports, provide a better interpretation of their crushing strength data. Experimental results show that two different fracture modes appear during the crushing test – one under bending configuration and one under crushing configuration – inducing a large scatter of the data. Moreover, a comparison with the 3PB test shows that the strength measured in crushing is lower and the scatter of the data is larger than the ones obtained in bending. This is a consequence of a Weibull size effect and of the presence of macro-defects within one type of the tested supports. It is concluded that an analysis of the fracture modes activated during crushing has to be carried out to obtain a correct distribution of the strength data. The presence of macro-defects within the microstructure of the supports decreases drastically the crushing strength, while their influence on the bending strength is more limited.
Design of a core-shell alumina catalyst support: Understanding the elementary mechanisms damaging coating during drying Chisa 2008 18th International Congress of Chemical and Process Engineering, 2008
Evaluation of cryotechniques for TEM observation of sols - Application to boehmite sols used in catalysts forming Revue De L Institut Francais Du Petrole, 1999
Influence of dispersed catalysts upon hydrogen utilization in the hydroconversion of a deasphalted vacuum residue American Chemical Society Division of Petroleum Chemistry Preprints, 1994
