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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.

An integrated approach of constitutive modeling and life prediction is presented through introduction of the integrated creep-fatigue theory (ICFT). The ICFT is formulated based on participating deformation and damage mechanisms, which not only describes the cyclic deformation behavior but also the life and fracture mode. Automotive exhaust system materials such as ductile cast iron and austenitic cast steel are used as example materials for demonstration in good agreement with experimental results and metallurgical examinations. This enlightens the understanding of the roles each mechanism plays in low-cycle fatigue (LCF) and thermomechanical (TMF) processes, thus helping material and component design specifically targeting the most damaging mechanism(s) encountered in service.

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.

Turbulent Jet Ignition is an advanced spark-initiated pre-chamber combustion system for otherwise standard spark ignition engines. Combustion in the main chamber is initiated by jets of partially combusted (reacting) pre-chamber products which provide a high energy ignition source. The resultant widely distributed ignition sites allow relatively small flame travel distances enabling short combustion durations and high burn rates. Demonstrated benefits include ultra lean operation (λ≻2) at part load and high load knock improvement. This study compared the knock limit of conventional spark ignition and pre-chamber jet ignition combustion with reducing fuel quality in a modern PFI engine platform. Seven PRF blends ranging from 93-60 octane were experimentally tested in a stoichiometric normally aspirated single-cylinder research engine at 1500 rev/min and ~WOT (98 kPa MAP).

The implementation and development efforts of lean NOx trap catalysts for heavy-duty applications decreased a number of years ago. Most heavy-duty engine manufacturers realized that the system complexity as well as the durability of such a system does not allow large volume production without significant risk. The current consensus of the heavy-duty community is that for 2010 the SCR system will be the prime path to meet the 0.2 g/bHPhr NOx emission standard, although this is subject to adequate infrastructure investment and progress. As a low volume manufacturer, in order to comply with the 2007 heavy-duty phase-in emission standards, General Engine Products (a subsidiary of AM General LLC) integrated a NOx adsorber system on the Optimizer 6500 engine. This engine features split combustion chamber design, rotary fuel injection pump and operates with EGR.

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.

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.

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.

Last year we presented the influence of pose on three-dimensional (3-D) shape classification in the context of a repeatability study. Meaning, that the subjects are repeatedly scanned 10 times and they attempt to assume the same pose each time. It was shown that changes due to a slight pose modification had no detrimental effects for shape classification. This paper discuss a second set of experiments, designed to test the stability of the geometric search engine in more extreme cases. The pose of the subjects between the scans are modified substantially, with an increasing amount of differences compared to the CAESAR protocol. Experimental results will be presented and discussed.

An On-line Technology Information System (OTIS) is currently being developed for the Advanced Life Support (ALS) Program. This paper describes the preliminary development of OTIS, which is a system designed to provide centralized collection and organization of technology information. The lack of thorough, reliable and easily understood technology information is a major obstacle in effective assessment of technology development progress, trade studies, metric calculations, and technology selection for integrated testing. OTIS will provide a formalized, well-organized protocol to communicate thorough, accurate, current and relevant technology information between the hands-on technology developer and the ALS Community. The need for this type of information transfer system within the Solid Waste Management (SWM) element was recently identified and addressed.

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 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.

It is not generally appreciated that the longitudinal position of a road vehicle model in a wind tunnel can have a significant influence on its measured aerodynamic drag. This paper explores the influence of the proximity of the end of the test section on measured aerodynamic drag, where the ‘end’ of the test section is defined by the start of the first diffuser or the end of a separate groundboard. Both flat plates and three-dimensional, automotive shapes were tested in three different model-scale and full-scale wind tunnels. It was found that the drag began to change from its upstream, undisturbed value when a vehicle model was closer than a distance of four times the square root of its base area from the end of the test section and that large changes occur when a vehicle model was closer than twice the square-root of its base area to the end of the test section. The effect is attributed to base pressure changes in the proximity of the diffuser or of the end of a groundboard.

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.