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Automotive suppliers provide multi-layer trims mainly made of porous materials. They have a real expertise on the characterization and the modeling of poro-elastic materials. A dozen parameters are used to characterize the acoustical and elastical behavior of such materials. The recent vibro-acoustic simulation tools enable to take into account this type of material but require the Biot parameters as input. Several characterization methods exist and the question of reproducibility and confidence in the parameters arises. A Round Robin test was conducted on three poro-elastic material with four laboratories. Compared to other Round Robin test on the characterization of acoustical and elastical parameters of porous material, this one is more specific since the four laboratories are familiar with automotive applications. Methods and results are compared and discussed in this work.

The reduction of vehicle exhaust particle emissions is a success story of European legislation. Various particle number (PN) counters and calibration procedures serve as tools to enforce PN emission limits during vehicle type approval (VTA) or periodical technical inspection (PTI) of in-use vehicles. Although all devices and procedures apply to the same PN-metric, they were developed for different purposes, by different stakeholder groups and for different target costs and technical scopes. Furthermore, their calibration procedures were independently defined by different stakeholder communities. This frequently leads to comparability and interpretation issues. Systematic differences of stationary and mobile PN counters (PN-PEMS) are well-documented. New, low-cost PTI PN counters will aggravate this problem. Today, tools to directly compare different instruments are scarce.

This paper touches on the mass transport phenomenon in the exhaust gas recirculation (EGR) of a gasoline engine air path. It presents the control-oriented model and control design of the burned gas ratio (BGR) transport phenomenon, witnessed in the intake path of an internal combustion engine (ICE), due to the redirection of burned gases to the intake path by the low-pressure EGR (LP-EGR). Based on a nonlinear AMESim® model of the engine, the BGR in the intake manifold is modeled as a state-space (SS) output time-delay model, or alternatively as an ODE-PDE coupled system, that take into account the time delay between the moment at which the combusted gases leave the exhaust manifold and that at which they are readmitted in the intake manifold. In addition to their mass transport delay, the BGRs in the intake path are also subject to state and input inequality constraints.

Autonomous driving systems and connected mobility are the next big developments for the car manufacturers and their suppliers during the next decade. To achieve the high computing power needs and fulfill new upcoming requirements due to functional safety and security, heterogeneous processor architectures with a mixture of different core architectures and hardware accelerators are necessary. To tackle this new type of hardware complexity and nevertheless stay within monetary constraints, high performance computers, inspired by state of the art data center hardware, could be adapted in order to fulfill automotive quality requirements. The European Processor Initiative (EPI) research project tries to come along with that challenge for next generation semiconductors. To be as close as possible to series development needs for the next upcoming car generations, we present a hybrid semiconductor system-on-chip architecture for automotive.

External Exhaust Gas Recirculation (EGR) provides an opportunity to increase the efficiency of turbocharged spark-ignition engines. Of the competing technologies and configurations, Low-Pressure EGR (LP-EGR) is the most challenging in terms of its dynamic behavior. Only some of the stationary feasible potential can be used during dynamic engine operation. To guarantee fuel consumption-optimized engine operation with no instabilities, a load point-dependent limitation of the EGR rate or alternatively an adaptation of the operating point to the actual EGR rate is crucial. For this purpose, a precise knowledge of efficiency and combustion variance is necessary. Since the operating state includes the actual EGR rate, it has an additional dimension, which usually results in an immense measuring effort.

In order to design vehicles with diminished gCO2/km emissions level, car manufacturers aim at reducing the weight of their vehicles. One of the solutions advocated by the automotive industry consists in the replacement of metallic parts by lighter systems made of polymer reinforced composites. Unfortunately, the numerical simulations set to evaluate the vibratory and acoustic performances of systems made of this kind of materials are often not sufficiently effective and robust so that convincing test/simulation correlations are rarely met. Indeed, for polymer-based materials, numerous parameters affect the vibroacoustic behavior. On the one hand, it is well known that the viscoelastic properties (Storage -Young- and dissipative moduli) of polymers depend on the temperature, loading frequency and sometimes the humidity content.

This paper is a case study from the TESSA project (French funded research program “Transfert des Efforts des Sources Solidiennes Actives”). The general frame of the work was to assess a collaborative design process between a car manufacturer and a major supplier using FE modelling and condensation of structure borne noise sources as an alternative to classic specification method for structure borne sources. Super elements from different FE commercial softwares have been used to assess the reliability of the method, the compatibility of the softwares and, most important, the relevance of applying a blocked force tensor to the component super element to predict the interior contribution of a component which is the originality of this work. The case study is an internal combustion engine cooling module (fan + shroud + exchangers) from VALEO including all assembly details (clips, decoupling elements) modelled under ABAQUS and its integration in a RENAULT Espace under NASTRAN.

From an acoustical point of view, the integration of seatbelt retractors in a vehicle is a real challenge that has to be met early in the vehicle development process. The buzz and rattle noise of seat belt retractors is a weak yet disturbing interior noise. Street irregularities excite the wheels and this excitation is transferred via the car body to the mounting location of the retractor. Ultimately, the inertia sensor of the locking mechanism is also excited. This excitation can be amplified by structural resonances and generate a characteristic impact noise. The objective of this paper is to describe a simulation method for an early development phase that predicts the noise-relevant low frequency local modes and consequently the contact of the retractor with the mounting panel of the car body via the finite element method.

Current regulatory developments aim for stricter emission limits, increased environmental protection and purification of air on a local and global scale. In order to find solutions for a cleaner combustion process, it is necessary to identify the critical components and parameters responsible for the formation of emissions. This work provides an evaluation process for particle formation during combustion of a modern direct injection engine, which can help to create new aftertreatment techniques, such as a gasoline particle filter (GPF) system, that are fit for purpose. With the advent of “real driving emission” (RDE) regulations, which include market fuels for the particulate number testing procedure, the chemical composition and overall quality of the fuel cannot be neglected in order to yield a comparable emission test within the EU and worldwide.

Due to its harmful effect on both human health and environment, soot emission is considered as one of the most important diesel engine pollutants. In the last decades, the industrial engine manufacturers have been able to strongly reduce its engine-out value by many different techniques, in order to respect the stricter emission norms. Simulation modeling has played and continues to play a key role for this purpose in the engine control system development. In this context, this paper proposes a new soot emission model for a direct injection diesel engine. This soot model is based on a zero-dimensional semi-physical approach coupled with a crank-angle resolved combustion model and a thermodynamic calculation of the burned gas products temperature. Furthermore, a multi linear regression model has been used to estimate the soot emissions as function of significant physical combustion parameters.

Partially Premixed Combustion (PPC) of fuels in the gasoline octane range has proven its potential to achieve simultaneous reduction in soot and NOX emissions, combined with high indicated efficiencies; while still retaining proper control over combustion phasing with the injection event, contrary to fully premixed strategies. However, gasoline fuels with high octane number as the commonly available for the public provide a challenge to ensure reliable ignition especially in the low load range, while fuel blends with lower octane numbers present problems for extending the ignition delay in the high load range and avoid the onset of knocking-like combustion. Thus, choosing an appropriate fuel and injection strategy is critical to solve these issues, assuring successful PPC operation in the full engine map.

Reducing NOx tailpipe emissions is one of the major challenges when developing automotive Diesel engines which must simultaneously face stricter emission norms and reduce their fuel consumption/CO2 emission. In fact, the engine control system has to manage at the same time the multiple advanced combustion technologies such as high EGR rates, new injection strategies, complex after-treatment devices and sophisticated turbocharging systems implemented in recent diesel engines. In order to limit both the cost and duration of engine control system development, a virtual engine simulator has been developed in the last few years. The platform of this simulator is based on a 0D/1D approach, chosen for its low computational time. The existing simulation tools lead to satisfactory results concerning the combustion phase as well as the air supply system. In this context, the current paper describes the development of a new NOx emission model which is coupled with the combustion model.

The worldwide automotive industry is currently preparing for a market introduction of hydrogen-fueled powertrains. These powertrains in fuel cell electric vehicles (FCEVs) offer many advantages: high efficiency, zero tailpipe emissions, reduced greenhouse gas footprint, and use of domestic and renewable energy sources. To realize these benefits, hydrogen vehicles must be competitive with conventional vehicles with regards to fueling time and vehicle range. A key to maximizing the vehicle's driving range is to ensure that the fueling process achieves a complete fill to the rated Compressed Hydrogen Storage System (CHSS) capacity. An optimal process will safely transfer the maximum amount of hydrogen to the vehicle in the shortest amount of time, while staying within the prescribed pressure, temperature, and density limits. The SAE J2601 light duty vehicle fueling standard has been developed to meet these performance objectives under all practical conditions.

The potential to reduce the cost of embedded software by standardizing the application behavior for Automotive Body and Comfort domain functions is explored in this paper. AUTOSAR, with its layered architecture and a standard definition of the interfaces for Body and Comfort application functions, has simplified the exchangeability of software components. A further step is to standardize the application behavior, by developing standard specifications for common Body and Comfort functions. The corresponding software components can be freely exchanged between different OEM/Tier-1 users, even if developed independently by multiple suppliers. In practice, individual OEM users may need to maintain some distinction in the functionality. A method of categorizing the specifications as ‘common’ and ‘unique’, and to configure them for individual applications is proposed. This allows feature variability by means of relatively simple adapter functions.

An innovative alternative to overcome the load limits of the early injection highly premixed combustion concept consists of taking advantage of the intrinsic characteristics of two-stroke engines, since they can attain the full load torque of a four-stroke engine as the addition of two medium load cycles, where the implementation of this combustion concept could be promising. In this frame, the main objective of this investigation focuses on evaluating the potential of the early injection HPC concept using a conventional diesel fuel combined with a two-stroke poppet valves engine architecture for pollutant control, while keeping a competitive engine efficiency. On a first stage, the HPC concept was implemented at low engine load, where the concept is expected to provide the best results, by advancing the start of injection towards the compression stroke and it was confirmed how it is possible to reduce NOX and soot emissions, but increasing HC and CO emissions.

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.

Lean NOx trap (LNT) and Selective Catalytic Reduction catalysts (SCR) are two leading candidates for diesel NOx after-treatment. Each technology exhibits good properties to reduce efficiently diesel NOx emissions in order to match the forthcoming EURO 6 standards. NOx reduction in LNT is made through a two-step process. In normal (lean) mode, diesel engine exhausts NOx is stored into the NOx trap; then when necessary the engine runs rich during limited time to treat the stored NOx. This operating mode has the benefit of using onboard fuel as NOx reducer. But NOx trap solution is restrained by limited active temperature windows. On the other hand, NH₃-SCR catalysts operate in a wider range of temperature and do not contain precious metals. However, NH₃-SCR systems traditionally use urea-water solution as reducing agent, requiring thus additional infrastructure to supply the vehicles with enough reducer. These pros and cons are quite restrictive in classical LNT or NH₃-SCR architecture.

For many years, bearing suppliers have been using the specific pressure to evaluate the fatigue risk of conrod bearings. However, modern engines have made the bearing more sensitive to various phenomena such as the thermal expansion or the elasticity of the conrod housing. These effects modify the stresses in the bearing layers and consequently fatigue risk. In this paper, we propose a new way to determine the bearing fatigue resistance. To achieve that, we analyze the elastic and plastic behavior of the bearing along the engine life. We detail and provide the analytical relationships which determine stresses in the overlay and in the substrate of the bearing in order to analyze their fatigue resistance. Various physical loads are taken into account such as the thermal load, the hydrodynamic pressure field, the fitting load, the free spread load. A good knowledge of the relationships between those physical phenomena helps to understand the mechanical behavior of the bearing.

This paper presents an after-treatment architecture combining a close coupled NOx trap and an under floor NOx trap. Instead of simply increasing the volume of the catalyst, we propose to broaden the active temperature window by splitting the LNT along the exhaust line. In order to design this architecture, a complete 1D model of NOx trap has been developed. Validated with respect to experimental data, this model has been useful to define the two volumes of LNT, making significant savings on the test bench exploitation. However, one of the main difficulties to operate the proposed architecture is the NOx purge and sulfur poisoning management. In order to optimize the NOx and sulfur purge launches, we have developed a control strategy based on an embedded reduced LNT model. These strategies have been validated on different driving cycles, by the means of simulation and of vehicle tests using rapid prototyping tools.

The introduction of alternative fuels is crucial to limit greenhouse gases. CNG is regarded as one of the most promising clean fuels given its worldwide availability, its low price and its intrinsic properties (high knocking resistance, low carbon content...). One way to optimize dedicated natural gas engines is to improve the CNG slow burning velocity compared to gasoline fuel and allow lean burn combustion mode. Besides optimization of the combustion chamber design, hydrogen addition to CNG is a promising solution to boost the combustion thanks to its fast burning rate, its wide flammability limits and its low quenching gap. This paper presents an investigation of different methane/hydrogen blends between 0% and 40 vol. % hydrogen ratio for three different combustion modes: stoichiometric, lean-burn and stoichiometric with EGR.