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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.

Driven by the desire to implement low-cost, high-efficiency NOx aftertreatment systems, such as Three Way Catalysts (TWC) or Lean NOx Traps (LNT), a novel 6-Stroke engine cycle was explored to determine the feasibility of implementing such a cycle on a compression ignition engine while continuing to deliver fuel efficiency. Fundamental questions regarding the abilities and trade-offs of a 6-stroke engine cycle were investigated for near-stoichiometric and lean operation. Experiments were performed on a single-cylinder 15-liter (equivalent) research engine equipped with flexible valvetrain and fuel injection systems to allow direct comparison between 4-stroke and 6-stroke performance across multiple hardware configurations. 1-D engine simulations with predictive combustion models were used to support, iterate on, and explore the 6-stroke operation in conjunction with the experiments.

Sensor selection for the control of modern powertrains is a recognised technical challenge. The key question is which set of sensors is best suited for an effective control strategy? This paper addresses the question through probabilistic modelling and Bayesian analysis. By quantifying uncertainties in the model, the propagation of sensor information throughout the model can be observed. The specific example is an abstract model of the slip behaviour of Selective Catalytic Reduction (SCR) DeNOx aftertreatment systems. Due to the ambiguity of the sensor reading, linearization-based approaches including the Extended Kalman Filter, or the Unscented Kalman Filter are not successful in resolving this problem. The stochastic literature suggests approximating these nonlinear distributions using methods such as Markov Chain Monte Carlo (MCMC), which is able in principle to resolve bimodal or multimodal results.

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.

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.

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 swivel-type hinge mount specified in SAE J180 has been the standard alternator mounting for many years. However, in the mid-1990's on-highway applications began to experience vibration related failures due to casting excitation. This led to the eventual development of a stationary “pad mount” system in combination with an automatic belt tensioner. This paper will review the system component life and benefits of pad mount, and proposes an industry mounting standard for further application usage.

The use of a partial flow sampling system (PFSS) to measure nonroad steady-state diesel engine particulate matter (PM) emissions is a technique for certification approved by a number of regulatory agencies around the world including the US EPA. Recently, there have been proposals to change future nonroad tests to include testing over a nonroad transient cycle. PFSS units that can quantify PM over the transient cycle have also been discussed. The full flow constant volume sampling (CVS) technique has been the standard method for collecting PM under transient engine operation. It is expensive and requires large facilities as compared to a typical PFSS. Despite the need for a cheaper alternative to the CVS, there has been a concern regarding how well the PM measured using a PFSS compared to that measured by the CVS. In this study, three PFSS units, including AVL SPC, Horiba MDLT, and Sierra BG-2 were investigated in parallel with a full flow CVS.

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.

Internal combustion (IC) engines that meet Tier 4 Final emissions standards comprise of multiple engine operation and control parameters that are essential to achieve the low levels of NOx and soot emissions. Given the numerous degrees of freedom and the tight cost/time constraints related to the test bench, application of virtual engineering to IC engine development and emissions reduction programmes is increasingly gaining interest. In particular, system level simulations that account for multiple cycle simulations, incylinder turbulence, and chemical kinetics enable the analysis of combustion characteristics and emissions, i.e. beyond the conventional scope of focusing on engine performance only. Such a physico-chemical model can then be used to develop Electronic Control Unit in order to optimise the powertrain control strategy and/or the engine design parameters.

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 a time and cost consuming way to physically develop Hybrid Electric Vehicle (HEV) supervisor controller due to the increasing complexity of powertrain system. This study aims to investigate the HEV supervisor controller development process using dSPACE midsize Hardware in the Loop simulation system (HIL) for HEV powertrain control. The prototyping controller was developed on basis of MircoAutoBox II, and an HIL test bench was built on midsize HIL machine for the purpose of verification. The feasibility and capability of HIL were attested by the prototyping control strategy and fault modes simulation. The proposed approach was demonstrated its effectiveness and applicability to HEV supervisor controller development.