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Diversifying energy resources and reducing greenhouse gas emissions are key priorities in the forthcoming years for the automotive industry. Currently, among the different solutions, sustainable biofuels are considered as one of the most attractive answer to these issues. This paper deals with the vehicle application of an innovative diesel fuel formulation using Ethanol to tackle these future challenges. The main goal is to better understand the impact of using biofuel blends on engine behavior, reliability and pollutants emissions. This alternative oxygenated fuel reduces dramatically particulate matter (PM) emissions; this paves the way to improve the NOx/PM/CO₂ trade-off. Another major interest is to avoid adding a particulate filter in the exhaust line and to avoid modifying powertrain and vehicle hardware and therefore to minimize the overall cost to fulfill upcoming emission regulations.

Facing the CO2 emission reduction challenge, the combination of downsizing and turbocharging appears as one of the most promising solution for the development of high efficiency gasoline engines. In this context, as knock resistance is a major issue, limiting the performances of turbocharged downsized gasoline engines, fuel properties are more than ever key parameters to achieve high performances and low fuel consumption's levels. This paper presents a combustion study carried out into the GSM consortium of fuel quality effects on the performances of a downsized turbocharged Direct Injection SI engine. The formulation of two adapted fuel matrix has allowed to separate and evaluate the impacts of three major fuel properties: Research Octane Number (RON), Motor Octane Number (MON) and Latent Heat of Vaporization (LHV). Engine tests were performed on a single cylinder engine at steady state operating condition.

The sustainability of Martian outposts development is strongly based on the capability of achieving a high level of autonomy both in terms of operations management and of resources availability. In situ production of consumables is a key point to allow humans to work and live on Mars avoiding or limiting the need for re-supplies of materials from Earth. Required consumables can be produced in situ exploiting the locally available resources, but also by means of green-houses and waste recycle systems. Dedicated robotic missions for in situ demonstration of this type of technologies are a fundamental step of the Martian In Situ Resources Utilization (ISRU) development roadmap. This paper is focused on the extraction of oxygen and fuels (e.g. methane) from the Martian atmosphere, and presents a feasibility study for a small technological demonstration plant.

The recent development of biofuel production worldwide is closely linked to GHG savings objectives and to regional agricultural policies. Many existing studies intend to evaluate the net non renewable energy and GHG savings associated to the various biofuel production pathways. However, there is no consensus on the results of those studies. The main explanations of variations among the results are the following: energy consumption and GHG emissions of the reference fossil pathway, data used for the representation of farming processes and biofuel production processes, accounting for carbon storage in agricultural soils, reference use of the land, choice of an allocation method in case of coproduction. There is a strong drive in the European Union for a certification on the sustainability of biofuel pathways.

Facing more and more stringent regulations, new solutions are developed to decrease pollutant emissions. One of them have shown promising and relevant results. It consists of the use of ethanol as a blending component for diesel fuel Nevertheless, the addition of ethanol to Diesel fuel affects some key properties such as the flash point. Consequently, Diesel blends containing ethanol become highly flammable at a temperature around ambient temperature. This study proposes to improve the formulation of ethanol based diesel fuel in order to avoid flash point drawbacks. First, a focus on physical and chemical properties is done for ethanol based diesel fuels with and without flash point improvement. Second, blends are tested on a passenger car diesel engine, under a wide operating range conditions from low load low speed up to maximum power. The main advantage of the ethanol based fuels generate low smoke level, that allows using higher EGR rate, thus leading to an important NOx decrease.

Among the last years, environmental concerns have raised the interest for biofuels. Ethanol, blended with gasoline seems particularly suited for the operation of internal combustion engines, and has been in use for severals years in some countries. However, it has a strong impact on engine performance, which is emphasized on recent engine architectures, with downsizing through turbocharging and variable valve actuation. Taking all the benefits of ethanol-blended fuel thus requires an adaptation of the engine management system. This paper intends to assess the effect of gasoline-ethanol blending from this point of view, then to describe a mean-value model of a fuel-flexible turbocharged PFI-SI engine, which will serve as a basis for the development of control algorithms. The focus will be in this paper on ethanol content estimation in the blend, supported by both simulation and experimental results.

An unified model with a single set of kinetic parameters has been proposed for modeling laminar flame velocities of several alkanes using detailed kinetic mechanisms automatically generated by the EXGAS software. The validations were based on recent data of the literature. The studied compounds are methane, ethane, propane, n-butane, n-pentane, n-heptane, iso-octane, and two mixtures for natural gas and surrogate gasoline fuel. Investigated conditions are the following: unburned gases temperature was varied from 300 to 600 K, pressures from 0.5 to 25 bar, and equivalence ratios range from 0.4 to 2. For the overall studied compounds, the agreement between measured and predicted laminar burning velocities is quite good.

The benefits of running on ethanol-blended fuels are well known, especially global CO₂ reduction and performances increase. But using ethanol as a fuel is not drawbacks free. Cold start ability and vehicle autonomy are appreciably reduced. These two drawbacks have been tackled recently by IFP and its partners VALEO and Cristal Union. This article will focus on the second one, as IFP had the responsibility to design the powertrain of a fully flex-fuel vehicle (from 0 to 100% of ethanol) with two main targets: reduce the fuel consumption of the vehicle and maintain (at least) the vehicle performances. Using a MPI scavenging in-house concept together with turbocharging, as well as choosing the appropriate compression ratio, IFP managed to reach the goals.

Quantitative fuel concentration visualizations are carried out to study the mixing process between fuel and air in Direct Injection (DI) Diesel like conditions, and generate high quality data for the validation of mixing models. In order to avoid the particular complication connected with fuel droplets, a gaseous fuel jet is investigated. Measurements are performed in a high-pressure chamber that can provide conditions similar to those in a diesel engine. A gas injection system able to perform injections in a high-pressure chamber with a good control of the boundary conditions is chosen and characterized. Mass flow rates typical of DI Diesel injection are reproduced. A Laser Induced Fluorescence technique requiring the mixing at high pressure of the fluorescent tracer, biacetyl, with the gaseous fuel, methane, is developed. This experimental technique is able to provide quantitative measurement of fuel concentration in high-pressure jets.

Dimethyl ether (DME) represents a promising fuel for heavy-duty engines thanks to its high cetane number, volatility, absence of aromatics, reduced tank-to-wheel CO2 emissions compared to Diesel fuel and the possibility to be produced from renewable energy sources. However, optimization of compression-ignition engines fueled with DME requires suitable computational tools to design dedicated injection and combustion systems: reduced injection pressures and increased nozzle diameters are expected compared to conventional Diesel engines, which influences both the air-fuel mixing and the combustion process. This work intends to evaluate the validity of two different combustion models for the prediction of performance and pollutant emissions in compression-ignition engines operating with DME. The first one is the Representative Interactive Flamelet while the second is the Approximated Diffusive Flamelet.

This work has the objective to present the extension of a novel quasi-dimensional model, developed to simulate the combustion process in diesel Compression Ignition (CI) engines, to describe this process when Dimethyl ether (DME) is used as fuel. DME is a promising fuel in heavy-duty CI engines application thanks to its high Cetane Number (CN), volatility, high reactivity, almost smokeless combustion, lower CO2 emission and the possibility to be produced with renewable energy sources. In this paper, a brief description of the thermodynamic model will be presented, with particular attention to the implementation of the Tabulated Kinetic Ignition (TKI) model, and how the various models interact to simulate the combustion process. The model has been validated against experimental data derived from constant-volume DME combustion, in this case the most important parameters analyzed and compared were the Ignition Delay (ID) and Flame Lift Off Length (FLOL).

Predictive combustion models are useful tools towards the development of clean and efficient engines operating with alternative fuels. This work intends to validate two different combustion models on compression-ignition engines fueled with Dimethyl Ether. Both approaches give a detailed characterization of the combustion kinetics, but they substantially differ in how the interaction between fluid-dynamics and chemistry is treated. The first one is single-flamelet Representative Interactive Flamelet, which considers turbulence-kinetic interaction but cannot correctly describe the stabilization of the flame. The second, named Tabulated Well Mixed, correctly accounts for local flow and mixture conditions but does not consider interaction between turbulence and chemistry. An experimental campaign was carried out on a heavy-duty truck engine running on DME at a constant load considering trade-off of EGR and SOI.