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A simulation method is presented for the analysis of combustion in spark ignition (SI) engines operated at elevated exhaust gas recirculation (EGR) level and employing multiple spark plug technology. The modeling is based on a zero-dimensional (0D) stochastic reactor model for SI engines (SI-SRM). The model is built on a probability density function (PDF) approach for turbulent reactive flows that enables for detailed chemistry consideration. Calculations were carried out for one, two, and three spark plugs. Capability of the SI-SRM to simulate engines with multiple spark plug (multiple ignitions) systems has been verified by comparison to the results from a three-dimensional (3D) computational fluid dynamics (CFD) model. Numerical simulations were carried for part load operating points with 12.5%, 20%, and 25% of EGR. At high load, the engine was operated at knock limit with 0%, and 20% of EGR and different inlet valve closure timing.

In scooter/motorbike engines coherent and stable tumble motion generation is still considered an effective mean in order to both reduce engine emissions and promote higher levels of combustion efficiency. The scientific research also assessed that squish motion is an effective mean for speeding up the combustion in a combustion process already fast. In a previous technical paper the authors demonstrated that for an engine having a high C/D ratio the squish motion is not only not necessary but also detrimental for the stability of the tumble motion itself, because there is a strong interaction between these two motions with the consequent formation of secondary vortices, which in turn penalizes the tumble breakdown and the turbulent kinetic energy production.

In this paper three-dimensional Large Eddy Simulations (i.e., LES) by using a PLIC-VOF method have been adopted to investigate the atomization process of round liquid jets issuing from automotive multi-hole injector-like nozzles. LES method is used to compute directly the effect of the large flow structure, being the smallest one modelled. A mesh having a cell size of 4 μm was used in order to derive a statistics of the detached liquid structures, i.e. droplets and ligaments. The latter have been identified by using an algorithm coded by authors. Cavitation modeling has not been included in the present computations. Two different mean injection nozzle flow velocities of 50 m/s and 270 m/s, corresponding to two mean nozzle flow Reynolds numbers of 1600 and 8700, respectively, have been considered in the calculations as representative of laminar and turbulent nozzle flow conditions.

This paper provides a survey about the consequences of a 42V Power Supply System for new vehicle projects, specially, its impact on directed project for Emerging Markets. At a first moment, it will be described new systems and its demand for additional power availability for future projects, such as electrical steering and brake systems; electrical air conditioning compressor; and electrical water and oil pumps. Following this subject, it will be presented possible alternatives for 14/42V Power Supply Systems, and also its impact over Power and Signal Distribution System components, such as connector, terminals, cables, relays, electrical centers, etc. Finally, the previous presented scenarios will be analyzed under a point of view for the Emerging Market demand for such new proposed systems, looking for best alternative driven.

A finite element model of a folded airbag with the module cover and steering wheel system was developed to estimate the injury numbers of a 5th percentile female dummy in an out-of-position (OOP) situation. The airbag model was correlated with static airbag deployments and standard force plate tests. The 5th percentile finite element dummy model developed by First Technology Safety Systems (FTSS) was used in the simulation. The following two OOP tests were simulated with the airbag model including a validated steering wheel finite element model: 1. Chest on air bag module for maximum chest interaction from pressure loading (MS6-D) and 2. Neck on air bag module for maximum neck interaction from membrane loading (MS8-D). These two simulations were then compared to the test results. Satisfactory correlation was found in both the cases.

A flash evaporation model is being developed to capture the effects of bubble nucleation and growth inside multi-hole injector nozzles to investigate the flash evaporation in fuel injector sprays in Gasoline Direct Injection (GDI). The 1D flash evaporation model is a key tool for providing the 3D Eulerian-Eulerian or Lagrangian spray simulation model with the right droplet size in order to properly predict the effect of degree of superheating on mixture formation. Super heating conditions are likely to be found under partial load conditions in GDI applications or they might be deliberately induced to enhance fuel atomization and vaporization. A quasi-1D nozzle flow model has been developed to help quantifying the effects of main physical and geometrical parameters in promoting fuel flash evaporation. This model is based on an weakly compressible homogenous two-phase mixture assumption. A non-equilibrium model is used to predict the vapour formation rate along the nozzle.

Traditional User/Maintenance Manuals provide useful information when dealing with simple machines. However, when dealing with complex systems of systems and highly miniaturized technologies, like UAVs, or with machines with millions of parts, a commercial aircraft is a case in point, new technologies taking advantage of Augmented Reality can rapidly and effectively support the maintenance operations. This paper presents a User/Maintenance Manual based on Augmented Reality to help the operator in the detection of parts and in the sequence to be followed to assemble/disassemble systems and subsystems. The proposed system includes a handheld device and/or an head mounted display or special goggles, to be used by on-site operators, with software management providing data fusion and overlaying traditional 2D user/maintenance manual information with an augmented reality software and appropriate interface.

The laminar burning speed is an important intrinsic property of an air-fuel mixture determining key combustion characteristics such as turbulent flame propagation. It is a function of the mixture composition (mixture fraction and residual gas mass fraction) and of the thermodynamic conditions. Experimental measurements of Laminar Flame Speeds (LFS) are common in literature, but initial pressure and temperature are limited to low values due to the test conditions: typical pressure values for LFS detection are lower than 25 bar, and temperature rarely exceeds 550 K. Actual trends in spark ignition engines are to increase specific power output by downsizing and supercharging, thus the flame front involves even more higher pressure and temperature since the beginning of combustion.

The emission and flow restriction characteristics of three different ceramic substrates with varying wall thickness and cell density (400 cpsi/6.5 mil, 600/4.3, and 600/3.5) are compared. These 106mm diameter substrates were catalyzed with similar amounts of washcoat and fabricated into catalytic converters having a total volume of 2.0 liters. A Pd/Rh catalyst technology was applied at a concentration of 6.65 g/l and a ratio of 20/1. Three sets of converters (two of each type) were aged for 100 hours on an engine dynamometer stand. After aging, the FTP performance of these converters were evaluated on an auto-driver FTP stand using a 2.4L, four-cylinder prototype engine and on a 2.4L, four-cylinder prototype vehicle. A third set of unaged converters was used for cold flow restriction measurements and vehicle acceleration tests.

California Ultra Low Emission Vehicle (ULEV) standards call for a significant reduction in the amount of harmful gases that enter the environment from vehicle exhaust. The Electrically Heated Catalyst (EHC) is a possible solution to reduce emissions. A competitive analysis benchmarking study was completed in order to find an optimum EHC design that will perform to ULEV standards. Four suppliers submitted samples and the EHC designs were rigorously tested for temperature, pressure drop, and emissions performance while being aged at different levels.

Hazard analysis plays an important role in the development of safety-critical systems. Hazard analysis techniques have been used in the development of conventional automotive systems. However, as future automotive systems become more sophisticated in functionality, design, and applied technology, the need for a more comprehensive hazard analysis approach has arisen. In this paper, we describe a comprehensive hazard analysis approach for system safety programs. This comprehensive approach involves applying a number of hazard analysis techniques and then integrating their results. This comprehensive approach attempts to overcome the narrower scope of individual techniques while obtaining the benefits of all of them.

The performance optimization of modern Spark Ignition engines is limited by knock occurrence: heavily downsized engines often are forced to work in the Knock-Limited Spark Advance (KLSA) range. Knock control systems monitor the combustion process, allowing to achieve a proper compromise between performance and reliability. Combustion monitoring is usually carried out by means of accelerometers or ion sensing systems, but recently the use of cylinder pressure sensors is also becoming frequent in motorsport applications. On the other hand, cylinder pressure signals are often available in the calibration stage, where SA feedback-control based on the pressure signal can be used to avoid damages to the engine during automatic calibration. A predictive real-time combustion model could help optimizing engine performance, without exceeding the allowed knock severity.

The European Commission is going to publish the new Euro7 standard shortly, with the target of reducing the impact on pollutant emissions due to transportation systems. Besides forcing internal combustion engines to operate cleaner in a wider range of operating conditions, the incoming regulation will point out the role of On-Board Monitoring (OBM) as a key enabler to ensure limited emissions over the whole vehicle lifetime, necessarily taking into account the natural aging of involved systems and possible electronic/mechanical faults and malfunctions. In this scenario, this work aims to study the potential of data-driven approaches in detecting emission-relevant engine faults, supporting standard On-Board Diagnostics (OBD) in pinpointing faulty components, which is part of the main challenges introduced by Euro7 OBM requirements.

A new adsorber system for reducing cold start HC emissions has been developed that offers a passive and simplified alternative to previous HC adsorber technologies. The series flow in-line adsorber concept combines existing catalyst technology with a zeolite based HC adsorber by simply incorporating one additional adsorber catalyst substrate into conventional catalytic converters without any valving, purging lines or special substrates. The HC adsorber catalyst consist of a durable zeolite, a washcoat binder, precious group metals and rare earth promoters on standard monolithic substrates. For selected vehicle applications, a single converter containing a light off catalyst, a catalyzed HC adsorber and a standard three-way catalyst can be used in the underfloor position. Even after severe engine aging, the vehicle FTP results show that this new technology remains effective in reducing the cold start HC emissions while providing good CO and NOx conversions.

Due to the integration of many interacting subsystems like hybrid vehicle management, energy management, distance management, etc. into the VCU platform the design steps for function development and calibration become more and more complex. This makes an aid necessary to relieve the development. Therefore, the aim of the proposed simulation-based development and calibration design is to improve the time-and-cost consuming development stages of modern VCU platforms. A simulation-based development framework is shown on a complex function development and calibration case study using an advanced powertrain concept with a plug-in hybrid electric vehicle (PHEV) concept with two electrical axles. Presenter Thomas Boehme, IAV GmbH

Due to the integration of many interacting subsystems like hybrid vehicle management, energy management, distance management, etc. into the VCU platform the design steps for function development and calibration become more and more complex. This makes an aid necessary to relieve the development. Therefore, the aim of the proposed simulation-based development and calibration design is to improve the time-and-cost consuming development stages of modern VCU platforms. A simulation-based development framework is shown on a complex function development and calibration case study using an advanced powertrain concept with a plug-in hybrid electric vehicle (PHEV) concept with two electrical axles.

Fault diagnosis for automotive systems is driven by government regulations, vehicle repairability, and customer satisfaction. Several methods have been developed to detect and isolate faults in automotive systems, subsystems and components with special emphasis on those faults that affect the exhaust gas emission levels. Limit checks, model-based, and knowledge-based methods are applied for diagnosing malfunctions in emission control systems. Incipient and partial faults may be hard to detect when using a detection scheme that implements any of the previously mentioned methods individually; the integration of model-based and knowledge-based diagnostic methods may provide a more robust approach. In the present paper, use is made of fuzzy residual evaluation and of a fuzzy expert system to improve the performance of a fault detection method based on a mathematical model of the engine.

A physically based simulation program developed by IAV makes a notable reduction of test bed measurements for the calibration of the cylinder charge calculation possible. Based upon geometric engine parameters and camshaft profiles, the cylinder charge is calculated from thermodynamic relationships taking into account the contribution of residual gas. After successful engine-specific calibration of the simulation model on the basis of a reduced set of test bed measurements, it is possible to calculate the cylinder air mass over the entire range of valve timing settings and operating points (engine load and speed). The simulation-generated “virtual” measurements can then be used for calibration of the control unit software over the entire operating range.

As vehicle development timelines continue to shorten, it is necessary for the full vehicle NVH engineer to be able to predict performance without actual prototypes. There has been significant advancement in the accuracy of finite element modeling techniques of trimmed bodies; however accuracy is still low in the road noise mid frequency range from 150-400Hz. Also, calculation times for these frequencies are long, with very large results files in some cases. To alleviate these limitations, a Hybrid approach has been used, where a finite element suspension and drive train model is coupled with a test based Frequency Response Function (FRF) model of the trimmed body. The predicted road noise level was compared to actual vehicle tests and exhibited excellent correlation.

It has been reported that lower extremity injuries represent a measurable portion of all moderate-to-severe automobile crash- related injuries. Thus, a simple tool to assist with the design of leg and foot injury countermeasures is desirable. The objective of this study is to develop a mathematical model which can predict load propagation and kinematics of the foot and leg in frontal automotive impacts. A multi-body model developed at the University of Virginia and validated for blunt impact to the whole foot has been used as basis for the current work. This model includes representations of the tibia, fibula, talus, hindfoot, midfoot and forefoot bones. Additionally, the model provides a means for tensioning the Achilles tendon. In the current study, the simulations conducted correspond to tests performed by the Transport Research Laboratory and the University of Nottingham on knee-amputated cadaver specimens.