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The success of stratified combustion is strongly determined by the injection and ignition system used. A large temporal and spatial variation of the main parameters - mixture composition and charge motion - in the vicinity of the spark location are driving the demands for significantly improved ignition systems. Besides the requirements for conventional homogeneous combustion systems higher ignition energy and breakdown voltage capability is needed. The spark location or spark plug gap itself has to be open and well accessible for the mixture to allow a successful flame kernel formation and growth into the stratified mixture regime, while being insensitive to potential interaction with liquid fuel droplets or even fuel film. For this purpose several different ignition concepts are currently being developed. The present article will give an ignition system overview for stratified combustion within Delphi Powertrain Systems.

The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer test variability during performance testing. In addition, dynamometer test results have been compared and correlated to vehicle testing. Even though there is already a vast amount of anecdotal evidence confirming the fact that different procedures generate different friction coefficients on the same brake corner, the availability of supporting data to the industry has been elusive up to this point. To overcome this issue, this paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory friction evaluation tests.

Goldilocks is a proposed serial communication protocol designed to find the “sweet spot” in trading off overhead, complexity, throughput, cost, and real time performance. Simple off line analysis of schedulability is a feature.. While backward compatible with CAN at the applications level, Goldilocks promises to be performance and feature competitive with FlexRay with less complexity and cost.

In order to allow continued production of the AM General Optimizer 6500 during MY 2007 through 2010 this IDI engine (Indirect Injection - swirl chamber) requires sophisticated aftertreatment controls while maintaining its fuel economy and durability. The main purpose of the development program was to retain the relatively inexpensive and simple base engine with distributor pump and waste-gated turbocharger, while adding hardware and software components that allow achievement of the phase-in emission standards for 2007 through 2010. The aftertreatment system consists of Diesel Oxidation Catalyst (DOC), NOx Adsorber Catalyst (or DeNOx Trap - DNT) and Diesel Particle Filter (DPF). In addition to the base hardware, an intake air throttle valve and an in-exhaust fuel injector were installed. The presented work will document the development process for a 2004 certified 6.5 l IDI heavy-duty diesel engine to comply with the 2007 heavy-duty emission standards.

An experiment was performed with a 1.3L catalytic converter design containing a front and rear catalyst each having a volume of 0.65 liters. This investigation varied the front catalyst parameters to study the effects of 1) substrate diameter, 2) substrate cell density, 3) Pd loading and 4) Rh loading on the FTP emissions on three different vehicles. Engine displacement varied from 2.4L to 4.7L. Eight different converters were built defined by a Taguchi L-8 array. Cold flow converter restriction results show the tradeoff in converter restriction between substrate cell density and substrate diameter. Vehicle FTP emissions show how the three vehicles are sensitive to the four parameters investigated. Platinum Group Metals (PGM) prices and Federal Test Procedure (FTP) emissions were used to define the emission value between the substrate properties of diameter and cell density to palladium (Pd) and rhodium (Rh) concentrations.

The focus of this study is to determine the effect of using B-20 (a blend of 20% soybean methyl ester biodiesel and 80% ultra low sulfur diesel fuel) on the combustion process, performance and exhaust emissions in a High Speed Direct Injection (HSDI) diesel engine equipped with a common rail injection system. The engine was operated under simulated turbocharged conditions with 3-bar indicated mean effective pressure and 1500 rpm engine speed. The experiments covered a wide range of injection pressures and EGR rates. The rate of heat release trace has been analyzed in details to determine the effect of the properties of biodiesel on auto ignition and combustion processes and their impact on engine out emissions. The results and the conclusions are supported by a statistical analysis of data that provides a quantitative significance of the effects of the two fuels on engine out emissions.

This paper proposes and evaluates improvements to a crash simulation of a fuel delivery module in a fuel tank. The simulations were performed in ANSYS/LS-DYNA. Deviations between the original simulation and test data were studied and reasons for the deviations hypothesized. These reasons stemmed from some of the simplifying assumptions of the model. Improvements consisted of incorporating plasticity and strain rate effects into the material models. Performance criteria were also directly incorporated into the material models such that non-performing portions of the model could be deactivated during the simulation. Finally, solid-fluid interactions were added into the simulation to include the momentum transfer from fuel to the fuel delivery module. It was previously thought that effects of a crash would be most severe on the module when the fuel tank was empty and the module was full with fuel.

Networking of active and passive safety is the fundamental basis for comprehensive vehicle safety. Situation-relevant information relating to driver reactions, vehicle behavior and traffic environment are fed into a crash probability calculator, which continually assesses the current crash risk and intervenes when necessary with appropriate measures to avoid a crash and reduce potential injuries. This provides effective protection not only for vehicle occupants but also for other, vulnerable road users. As this functionality up till now only relates to the vehicle itself, the next logical step is enhancement leading to the ultimate goal in safety performance, telematics. The integration of this embedded, in-vehicle wireless communication system allows Car-to-Car (C2C) and Car-to-Infrastructure (C2I) functionality for, e.g. hazard warning. This is an integral element of the cascaded ContiGuard® protection measures.

The AUTomotive Open System ARchitecture (AUTOSAR) Development Partnership has published early 2008 the specifications Release 3.0 [1], with a prime focus on the overall architecture, basic software, run time environment, communication stacks and methodology. Heavy developments have taken place in the OEM and supplier community to deliver AUTOSAR loaded cars on the streets starting 2008 [2]. The 2008 achievements have been: Improving the specifications in order to secure the exploitation for body, chassis and powertrain applications Adding major features: safety related functionalities, OBD II and Telematics application interfaces.

Embedded software is a software system that permanently resides in a device whose operations it controls. Typically, embedded systems are housed on flash memory or ROM chip and may be found in systems like cellular phones, household and office appliances having digital interfaces, medical equipment, automotive components, avionics etc. The fundamental problem facing the design of embedded systems is heterogeneity. Multiple styles of algorithms (e.g. signal processing, communications, and controls) are implemented using a variety of technologies (e.g., digital signal processors, microcontrollers, field-programmable gate arrays, application-specific integrated circuits, and real-time operating systems).Other challenges in automotive development are increasing requirements and therefore increasing size and complexity of the code, development and management of offshore / muti-site software development to reduce costs.

Signal processing incorporating Artificial Neural Networks (ANN) has been shown to be well suited for modeling engine-related performance indicators [ 1 , 2 , 3 ] that require multi-dimensional parametric calibration space. However, to obtain acceptable accuracy, traditional ANN implementation may require processing resources beyond the capability of current engine controllers. This paper explores the practicality of implementing an ANN-based algorithm performing real-time calculations of the volumetric efficiency (VE) for an engine with variable valve actuation (phasing and lift variation). This alternative approach was considered attractive since the additional degree of freedom introduced by variable lift would be cumbersome to add to the traditional multi-dimensional table-based representation of VE.

Worldwide scrutiny of the global warming impact of R-134a has presented the automotive industry with a pressing challenge to search for suitable alternative refrigerant(s). HFC-152a, referred to as R-152a in the air conditioning and refrigeration industry, is touted as an alternative [1, 2] to R-134a because of its lower global warming potential (GWP). R-152a is more environmentally benign than R-134a with GWP of 120 versus 1300. This paper is a follow up to the work on the potential applications of R-152a presented at the 2003 Vehicle Thermal Management Systems Conference (VTMS6) [3]. It documents continuing progress in applying R-152a to vehicle climate control systems. The paper compares R-152a cooling performance and energy performance to comparable R-134a system designs, including direct and indirect expansion systems. Also discussed are efforts to provide safe system operation with R-152a refrigerant.

The development and preliminary testing of an algorithm that detects impending rollover is described. The algorithm is intended for use in conjunction with active chassis systems to prevent some types of rollovers. Several methods of estimating roll angle and roll rate from physical principles using available sensors are presented. Advantages and drawbacks of each method and their ranges of reliable operations are discussed. An approach using a closed-loop adaptive observer for estimating roll angle and roll rate of vehicle body with respect to the road is proposed. Performance and robustness of the estimator are evaluated through numerical simulations and vehicle testing, using various scenarios, including maneuver induced and road induced body roll. The estimates are shown to be consistently superior to those obtained from other methods. A roll index is proposed, which uses the estimated roll angle and other signals to indicate rollover danger.

The relationship between engine oil formulations and catalyst performance was investigated by comparatively testing five engine oils. In addition to one baseline production oil with a calcium plus magnesium detergent system, the remaining four oils were specifically formulated with different additive combinations including: one worst case with no detergent and production level zinc dialkyldithiophosphate (ZDTP), one with calcium-only detergent and two best cases with zero phosphorus. Emissions performance, phosphorus loss from the engine oil, phosphorus-capture on the catalyst and engine wear were evaluated after accumulating 100,000 miles of taxi service in twenty vehicles. The intent of this comparative study was to identify relative trends.

In the research project between the Institute of Automotive Engineering (FZD) of the Technische Universität Darmstadt (TUD) and Continental Teves AG & Co. oHG a new modeling concept has been developed. With the aim to enhance the current development process, the brake caliper is modeled based on coupled rigid bodies integrated into a nonlinear system model. Using an explicit interface definition, the number of degrees of freedom is minimized and the calculation of caliper performance is possible over a wide range of parameters. Compared to models based on the Finite Element Method (FEM), fully parameterized geometry from CAD is not necessary, thus the caliper can be optimized for a variation of its geometrical and physical parameters. With this modeling approach, typical performance criteria such as caliper fluid displacement, hysteresis, uneven pad wear and residual torque can be calculated in a virtual bench test.

In this paper, the design and development of an adaptive Energy Absorbing (EA) steering column using systems and virtual engineering approach is presented. An adaptive EA column adapts to the load characteristics based on crash severity, the occupant mass, the seat position and seat belt usage. The EA device provides the intended load profile during column loading. The design of this device used in steering column is achieved by virtual prototyping using LS-DYNA3D finite element (FE) code in analysis and synthesis based on component and subsystem models. The load-carrying member in the EA device is a metallic strap and the load carrying capacity of this strap is determined for various design parameters such as the strap geometry, thickness, material and the friction between the strap and the housing. Correlation of the analysis with limited dynamic pull test of the strap is shown. Further, the results of a subsystem FE mini-sled model using a Blak tuffy are presented.

The purpose of the present paper is to develop an engine simulation tool in a commercial CFD code to study the spray and mixing process that can be used to access the performance of a Gasoline Direct Injection (GDI) engine. The ignition, combustion and pollutant formation are strongly dependent on the quality of the fuel-air mixture. The fuel is injected directly into the combustion chamber by high-pressure fuel injector. The fuel atomization and evaporation process takes place due to the interaction of the small fuel particles generated by the injector and the in-cylinder air motion. Experimental study on the spray and mixing process is difficult and expensive, which has been recognized as a major obstacle towards the optimization of the combustion chamber geometry, engine components and the injection strategies.

Driver assistance features have been introduced to the market focusing on basic, independent functional scenarios. The trend is showing that these kinds of products are facing more and more complex scenarios and we are transitioning from single independent functions to a strongly networked system. Some of the drivers for future autonomous vehicles are 360° monitoring by active safety technology and V2X (vehicle to vehicle or vehicle to infrastructure) communication. In the past vehicles were strictly operated by the driver. Advanced driver assistance products added so called feedback features like lane departure warning, forward collision warning, and blind spot monitoring. First steps towards semi-autonomous driving started with the development of active support functions like adaptive cruise control or lane keeping support. Collision mitigation with various authority levels is the next milestone towards automation followed by other, even more advanced, features.

A Robust Engineering experiment was performed to determine the effects PGM loading and placement on the FTP emissions of a 4 cylinder 2.4L and two 8 cylinder 4.7L vehicles. 1.3L catalytic converters were used containing a front and rear catalyst of equal volume. The experiment is defined by a Taguchi L-8 array. Eight different combinations of catalyst PGM loadings were aged and evaluated. Results show that nmHC and NOx emissions are predominately affected by the PGM loading of the front catalyst. The rear catalyst is insensitive to either Pt or Pd which can be used at low concentrations. Results also compare the benefits of Pd and Rh to reduce emissions. Confirmation runs suggest that significant reductions in PGM cost can be achieved over baseline designs.

A new family of automotive three-way conversion (TWC) catalyst technologies has been developed using a Precision Metal Addition (PMA) process. Precious metal (PGM) fixation onto the support occurs during the PMA step when the PGM is added to the slurry immediately prior to application to the monolith substrate. PMA slurries can be prepared with high precision and the slurry manufacturing process is greatly simplified. Further, it has been found that with the use of new generation washcoat (WC) materials, the same WC composition can be used for all three PGMs - Pt, Pd & Rh. Negative interactions between Pd and Rh in the same WC layer do not occur, providing advantages over older technologies. Thus, new WC compositions coupled with the PMA process offers precious metal flexibility. This FlexMetal family of catalyst technologies includes single layer Pd-only, Pd/Rh and Pt/Rh and dual layer bi-metal Pd/Rh and Pt/Rh and tri-metal Pt/Pd/Rh.