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This paper proposes a method to detect an intake manifold leakage for a Diesel engine with a dual loop EGR system. The intake manifold leak has a strong impact on the engine performances by changing the intake manifold burned gas ratio. This fault is analyzed according to the control structure used and also according to the EGR operating mode. The paper proposes a diagnosis algorithm to detect the intake manifold leak in sequential or simultaneous use of the two EGR paths. The sensors considered are the mass air flow meter, the intake manifold pressure sensor, the exhaust equivalence ratio sensor and the differential pressure sensor (across the HP EGR valve). The diagnosis is based on a criteria that uses the redundancy between these sensors and air system models or estimators. The diagnosis threshold depends on the engine operating conditions as well as the sensor or model dispersions.

This paper introduces a research work on the air loop system for a downsized two-stroke two-cylinder diesel engine conducted in framework of the European project dealing with the POWERtrain for Future Light-duty vehicles - POWERFUL. The main objective was to determine requirements on the air management including the engine intake and exhaust system, boosting devices and the EGR system and to select the best possible technical solution. With respect to the power target of 45 kW and scavenging demands of the two-cylinder two-stroke engine with a displacement of 0.73 l, a two-stage boosting architecture was required. Further, to allow engine scavenging at any operation, supercharger had to be integrated in the air loop. Various air loop system layouts and concepts were assessed based on the 1-D steady state simulation at full and part load with respect to the fuel consumption.

3D simulations of internal combustion engines are usually based on statistical approaches (RANS) that may not allow predicting cycle-to-cycle variations (CCV) or transient speeds because part of this information is lost by the averaging procedure. To simulate such phenomena, it requires time resolved approaches. Therefore, large eddy simulation (LES), which only involves a spatial averaging, appears to be a very promising tool. An LES approach is applied to simulate the flow field inside one cylinder taken from a real four-valve diesel engine mounted on an experimental particle image velocimetry (PIV) bench. Preliminary tests are carried out to evaluate the industrial code capabilities. A multi-cycle calculation is computed in cold flow, in order to evaluate its ability to simulate cycle-to-cycle variations (CCV).

To reduce greenhouse gas emissions such as CO2, automakers are actively pursuing alternative propulsion systems. Improvements to current engine technology are being investigated along with new power plant technologies. Fuel Cell Vehicles offer an exciting option by producing electric power through a reaction that combines hydrogen and oxygen to make water. However, hydrogen storage onboard vehicles and construction of an expensive hydrogen distribution and fueling infrastructure remain as challenges today. In addition, greenhouse gas emissions from the production of hydrogen must be considered since most hydrogen is currently produced from non-renewable sources. While these issues are being worked on, Renault has chosen to pursue a fuel cell vehicle with a fuel processor that converts gasoline and other liquid fuels to hydrogen onboard the vehicle.

The EPEFE research programme is the largest European investigation of the effects of vehicle/fuel technologies on exhaust emissions. This paper consolidates and summarizes the more than 500 000 data points and compares and contrasts the effects of fuel properties in different vehicles and engines. While the relationships between fuel properties/engine technologies and exhaust emissions are complex, it has been possible to develop equations that model these interactions. The paper demonstrates how the output of EPEFE has been used to predict inventories of emissions from the european traffic for the period 2000-2010. The need for continuing co-operation between the Oil/Auto Industries and the Legislative Authorities to further understand the complex relationships is discussed.

A consortium of CONCAWE, EUCAR and the EU Commission's JRC carried out a Well-to-Wheels analysis of a wide range of automotive fuels and powertrains. The study gives an assessment of the energy consumption and greenhouse gas emissions for each pathway. It also considers macroeconomic costs and the market potential of alternative fuels.

Four Diesel vehicles and two gasoline ones are used to determine the repeatability of the particle number and size measurements. Two analytical techniques are used: Scanning Mobility Particle Sizer (SMPS) and Electrical Low Pressure Impactor (ELPI). The influence of technology (Euro2 and Euro3, Diesel and gasoline vehicles, Diesel Particulate Filter (DPF), Gasoline Direct Injection (GDI)) and speed on the particle number and size is presented in the case of steady speeds and the European Driving Cycle (EDC). The repeatability of these measurements is determined at the entire particle distribution. The global 1.96*Standard Deviation (SD) of the median diameter, determined by SMPS, is 8 nm. The median diameter is difficult to be determined in several cases due to the flat profiles of the emitted particles. The global 1.96*Relative Standard Deviation (RSD) of the particle number presents a U-like curve, with a minimum value (55-57%) at about 100 nm.

The Particulate Measurement Programme (PMP) works on the identification of a method to replace or complete the existing particle mass (PM) measurement method. The French PMP subgroup, composed by IFP, PSA Peugeot-Citroën, Renault and UTAC, proposes an improved gravimetric method for the measurement of emitted particles, and conducted an inter-laboratory test to evaluate its performances. The technical programme is based on tests carried out on a Euro3 Diesel passenger car (PC), tested on the New European Driving Cycle (NEDC). To achieve low particulate matter (PM) emissions, the EGR is disconnected and a paraffinic fuel is used. The regulated pollutants are also measured. It is shown that the multiple filter weighing and a 0.1 μg balance instead of a 1 μg one are not necessary, as the first weighing and the 1 μg balance performances are satisfactory for type-approval purposes.

Electrical Low Pressure Impactor (ELPI) is often employed to measure the particle number and size distribution of internal combustion engines exhaust gas. If appropriate values of particle density are available, the particle mass can be estimated by this method. Exhaust particles of three Euro3 passenger cars (one gasoline operating under stoichiometric conditions, one Diesel and one Diesel equipped with Diesel Particulate Filter) are measured using the current European regulations (gravimetric method on the are New European Driving Cycle) and estimated by ELPI particle number and size distribution. Different values for particle density are used to estimate the particle mass using all ELPI stages or only some of them. The results show that the particle mass estimated by ELPI is well correlated with the mass determined by filters for PM emissions higher than 0.025 g/km. This correlation is not very good at lower emissions.

An extensive research program involving the French passenger car and heavy-duty (HD) vehicles manufacturers, sponsored by ADEME and realized by IFP, aimed to characterize in terms of size and composition the particulate emitted by the different engine technologies currently or soon available. The impact of engine settings and fuel composition was also studied. Numerous information was collected in this HD study revealing that fuel composition and particularly non-conventional fuels and engine settings strongly impact the particulate concentration and size distribution. Nucleation is likely to occur when there is less adsorption matter, for instance when post-injection is used or EGR is removed. Particulate composition, particularly PAH and sulfates content, is weakly bound to the size. Mineral elements distribution depends on their origin, lubrication oil or engine wear.

Atomizing systems must be able to form sprays with predetermined characteristics. There are affected by the shape of the injector as well as external conditions. Thus, in order to avoid numerous experiments, this is necessary to develop predictive atomization models able to deal with the complete atomization process. This can be done using a Eulerian model for primary break-up. This approach describes the flow continuously from inside the injector to the dispersed spray region. In this paper the Eulerian multiphase approach and the Eulerian single-phase approach are compared and the results lead to an intermediate quasi-multiphase approach for describing the spray core. Finally a transition zone permits to represent the diluted spray region by using the classical Lagrangian approach to benefit of the experience accumulated on this method, in particular for the vaporization and the combustion.

BMW has undertaken a comprehensive program including laboratory simulation rig tests, engine dynamometer and fleet evaluations to evaluate the influence of mechanical and fuel variables on induction system deposits in modern port fuel injected (PFI) spark ignition engines. The primary focus of the program has been the deposit buildup on intake valves (IVD) and associated driveability impacts. Initial investigations of engine modifications yielded only marginal improvements relative to deposit build-up and, therefore this led to investigations of the effect of gasolines and additives. Fuel quality, type, quantity of additives and alcohol content have all been found to be major contributing factors to intake valve deposition. In addition, intake valve deposit weight has been directly related to warm-up phase driveability concerns using a newly developed driveability procedure.

The idea of keeping a vehicle safe and secure throughout its whole life cycle, as well as having the opportunity to add functionality after initial delivery, is the key motivation behind automotive software updates. Today, safety or security issues that appear after vehicle delivery need to be resolved by starting a recall campaign. These campaigns require the vehicle user to visit a car repair workshop to get an update. Over The Air (OTA) software updates, being location-independent, can pave the way for higher update frequencies and more efficiency regarding customer satisfaction, resource consumption as well as safety and security. In this paper we analyze requirements for OTA software updates phrased in various standards and regulations as well as in existing development and type approval processes. Prevailing challenges for OTA updates are extracted to identify necessary activities and artifacts within the procedure.

The new generation of drive-by-wire systems currently under development has demanding requirements on the electronic architecture. Functions such as brake-by-wire or steer-by-wire require continued operation even in the presence of component failures. The electronic architecture must therefore provide fault-tolerance and real-time response. This in turn requires the operating system and the communication layer to be predictable, dependable and composable. It is well known that this properties are best supported by a time-triggered approach. A consortium consisting of German and French car manufacturers and suppliers, which aims at becoming a working group within the OSEK/VDX initiative, the OSEKtime consortium, is currently defining a specification for a time-triggered operating system and a fault-tolerant communication layer.1 The operating system and the communication layer are based on applicable interfaces of the OSEK/VDX standard.

The purpose of this paper is to present the results of a study on the exhaust junctions geometry. Twelve three-branch junctions of different geometry have been tested on a single cylinder engine. The parameters studied have been exhaust junction outlet-to-inlet diameter ratio, length, angle between inlet branches and the existence of a reed separating inlet branches. An analysis of the pressure waves amplitude (incident, reflected and transmitted) obtained from instantaneous pressure measurements in some locations around the junction has been carried out. The analysis of results shows that junction length has a low influence on its behavior. The ratio between inlet and outlet branches diameters increases both reflection and directionality (avoiding pressure wave transmission to the adjacent branch). The existence of a reed separating the inlet flows may increase directionality with moderate pressure losses if the throat area is not reduced.

This presented paper deals with NOx trap sulphur poisoning and its regeneration. Sulphur poisoning has been studied with different SO2 gas concentrations under laboratory and engine test bench conditions. The sulphur poisoning studies have shown that the different NOx-traps available in the market have different behaviours toward SO2 poisoning and are all very sensitive to it. The results outline a non linear relationship of the NOx trap sulphur poisoning as a function of SO2 concentration. For instance, engine bench tests show that with a 50 and a 110ppm sulphur containing gasoline, a decrease of 50% in the NOx-trap storage capacity is respectively observed after 20 and 15 hours. With a gasoline containing 20ppm of sulphur, the same deactivation level is observed after 90 hours.

Laboratory and vehicle tests were carried out to investigate behaviour and potentiality of NOx-trap catalytic system in Diesel conditions. Three main aspects were studied. The first one deals with the NOx storage capacity of adsorber under laboratory and vehicle conditions, especially regarding the influence of driving conditions. The second one focuses on the regenerability of different materials. At length, special attention is devoted to the sulphur poisoning rate. A representative laboratory test method was built up, to evaluate NOx storage capacity under Diesel conditions. It is shown that NOx adsorption occurs from 100 to 400°C. Low temperature activity (100 to 250°C) is conditioned by low NOx flow emission, mainly due to the use of high EGR rate. Higher temperatures lead to an increase in the intrinsic NOx Storage capacity of the material, but are also accompanied by high NOx concentration and space velocity.

The electric power required in automotive systems is quickly reaching a level that significantly impacts costs and fuel consumption. This drives the need to reconsider an electric energy management function. Fast evolving factors such as increasing power usage, and stricter engine management and reliability requirements necessitate a global vehicle approach to energy management. Innovations such as new powernet concepts (42 volt or dual voltage systems), new component technologies (high-performance energy storage, high efficiency and controllable generators), and global electronic and software architecture concepts will enable this new energy management concept. This paper describes key issues to maximize energy availability with reasonable components.

This paper presents an investigation on the experimental determination of some characteristics of the flow issuing from a swirl injector dedicated to direct-injection spark-ignited engines. The reproducibility, from one injection to another, of the temporal evolution of the liquid flow characteristics during the opening of the injector was investigated. This was achieved by using a high-speed film camera set at 8,000 images/s. The resulting visualizations allowed us to measure the evolution of the penetration length and velocity as well as of the liquid cone angle. It was found that the spray produced is a low momentum spray whose penetration length and velocity are small. The good reproducibility of the temporal evolution of the liquid flow characteristics has been obtained, except for the liquid cone angle during the opening stage. A fast-shutter video camera was also used to make images of the early development of the issuing liquid flow.