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The papers in this collection cover recent advances in research, development and engineering of hybrid, plug-in hybrid, and electric powertrains and architectures with particular emphasis on new and near-production technologies.

This collection covers advances in the development and application of models and tools involved in multi-dimensional engine modeling: advances in chemical kinetics, combustion and spray modeling, turbulence, heat transfer, mesh generation, and approaches targeting improved computational efficiency. Papers employing multi-dimensional modeling to gain a deeper understanding of processes related to turbulent transport, transient phenomena, and chemically reacting, two-phase flows are included in this collection.

The papers in this collection cover topics regarding new CI and SI engines and components. This includes analytical, experimental, and computational studies covering hardware development, as well as design and analysis techniques.

Classical diesel engine combustion with relatively short ignition delay, including papers dealing with low CR and high EGR calibrations. Papers describing experiments and test data, simulation results focused on applications, fuel/additive effects, combustion control, and mode change are part of this collections.

Papers focusing on in-cylinder processes of classical diesel engine combustion with relatively short ignition delay, including papers dealing with low CR and high EGR calibrations. Subject matter may include both simulation results and experimental work, including applications of optical diagnostics, with emphasis on in-cylinder spray, evaporation, mixing, pollutant formation/destruction, or any other in-cylinder phenomena.

Papers in this subscription deal with classical diesel engine combustion with relatively short ignition delay, including papers dealing with low CR and high EGR calibrations. Papers describing experiments and test data, simulation results focused on applications, fuel/additive effects, combustion control, and mode change are also included.

Papers in the session cover zero-dimensional, one-dimensional, and quasi-dimensional models for simulation of SI and CI engines with respect to: engine breathing, boosting, and acoustics; SI combustion and emissions; CI combustion and emissions; fundamentals of engine thermodynamics; numerical modeling of gas dynamics; thermal management; mechanical and lubrication systems; system level models for controls; and system level models for vehicle fuel economy and emissions predictions.

The papers in this collection cover topics regarding new CI and SI engines and components. This includes analytical, experimental, and computational studies covering hardware development, as well as design and analysis techniques.

The 7 papers in this technical paper collection focus on kinetically controlled combustion and HCCI.

The 14 papers in this technical paper collection are devoted to experimental and computational work in the area of diesel fuel injection systems and sprays. Topics include: spray characterization, cavitation, multi-phase jet modeling, CFD models for spray processes, wall films and impingement, hydraulic circuit analysis, and dissolved gas effects.

The 10 papers in this technical paper collection cover all system-level engine technologies and design/analysis/testing techniques related to engine system design. Coverage includes the areas of emissions, fuel economy, combustion, calibration/control, fuel systems, valvetrain integration, thermodynamic cycles, air/charging systems, EGR systems, and engine brakes. It also includes system-level integration issues for the engine/powertrain, and steady-state/transient performance for on/off-road and heavy/light-duty applications.

Papers in the session cover zero-dimensional, one-dimensional, and quasi-dimensional models for simulation of SI and CI engines with respect to: engine breathing, boosting, and acoustics; SI combustion and emissions; CI combustion and emissions; fundamentals of engine thermodynamics; numerical modeling of gas dynamics; thermal management; mechanical and lubrication systems; system level models for controls; and system level models for vehicle fuel economy and emissions predictions.

The papers in this collection focuses on technologies such as advanced and partially mixed combustion, cooled EGR boosting, ignition and direct injection technologies, pressure boosting, intelligent combustion, thermal efficiency, fully variable valvetrains, and other new and developing technologies.

The 32 papers in this technical paper collection cover zero-dimensional, one-dimensional, and quasi-dimensional models for simulation of SI and CI engines with respect to: engine breathing, boosting, and acoustics; SI combustion and emissions; CI combustion and emissions; fundamentals of engine thermodynamics; numerical modeling of gas dynamics; thermal management; mechanical and lubrication systems; system level models for controls; system level models for vehicle fuel economy and emissions predictions.

Four of these Particulate Reduction Systems (PMS) were tested on a passenger car and one of them on a HDV. Expectation of the research team was that they would reach at least a PM-reduction of 30% under all realistic operating conditions. The standard German filter test procedure for PMS was performed but moreover, the response to various operating conditions was tested including worst case situations. Besides the legislated CO, NOx and PM exhaust-gas emissions, also the particle count and NO2 were measured. The best filtration efficiency with one PMS was indeed 63%. However, under critical but realistic conditions filtration of 3 of 4 PMS was measured substantially lower than the expected 30 %, depending on operating conditions and prior history, and could even completely fail. Scatter between repeated cycles was very large and results were not reproducible. Even worse, with all 4 PMS deposited soot, stored in these systems during light load operation was intermittently blown-off.

Premixed Charge Compression Ignition (PCCI), a Low Temperature Combustion (LTC) strategy for diesel engines is of increasing interest due to its potential to simultaneously reduce soot and NOx emissions. However, the influence of mixture preparation on combustion phasing and heat release rate in LTC is not fully understood. In the present study, the influence of injection timing on mixture preparation, combustion and emissions in PCCI mode is investigated by experimental and computational methods. A sequential coupling approach of 3D CFD with a Stochastic Reactor Model (SRM) is used to simulate the PCCI engine. The SRM accounts for detailed chemical kinetics, convective heat transfer and turbulent micro-mixing. In this integrated approach, the temperature-equivalence ratio statistics obtained using KIVA 3V are mapped onto the stochastic particle ensemble used in the SRM.

The goal of this research is to investigate the physical parameters of stoichiometric operation of a diesel engine under a light load operating condition (6∼7 bar IMEP). This paper focuses on improving the fuel efficiency of stoichiometric operation, for which a fuel consumption penalty relative to standard diesel combustion was found to be 7% from a previous study. The objective is to keep NOx and soot emissions at reasonable levels such that a 3-way catalyst and DPF can be used in an aftertreatment combination to meet 2010 emissions regulation. The effects of intake conditions and the use of group-hole injector nozzles (GHN) on fuel consumption of stoichiometric diesel operation were investigated. Throttled intake conditions exhibited about a 30% fuel penalty compared to the best fuel economy case of high boost/EGR intake conditions. The higher CO emissions of throttled intake cases lead to the poor fuel economy.

Exhaust gas recirculation, fuel injection strategy and boost pressure are among the key enablers to attain low NOx and soot emissions simultaneously on modern diesel engines. In this work, the individual influence of these parameters on the emissions are investigated independently for engine loads up to 8 bar IMEP. A single-shot fuel injection strategy has been deployed to push the diesel cycle into low temperature combustion with EGR. The results indicated that NOx was a stronger respondent to injection pressure levels than to boost when the EGR ratio is relatively low. However, when the EGR level was sufficiently high, the NOx was virtually grounded and the effect of boost or injection pressure becomes irrelevant. Further tests indicated that a higher injection pressure lowered soot emissions across the EGR sweeps while the effect of boost on the soot reduction appeared significant only at higher soot levels.

With recent increases in global fuel prices there has become a growing interest in expanding the use of diesel engines in the transportation industry. However, new engine development is costly and time intensive, requiring many hours of expensive engine tests. The ability to accurately predict an engine's performance based on existing models would reduce the expense involved in creating a new engine of different size. In the present study experimental results from two single-cylinder direct injection diesel engines were used to examine previously developed engine scaling models. The first scaling model was based on an equal spray penetration correlation. The second model considered both equal spray penetration and flame lift-off length. The engines used were a heavy-duty Caterpillar engine with a 2.44L displacement and a light-duty GM engine with a 0.48L displacement.

The present paper describes an experimental study on the effect of the compression ratio on the performance of a LD diesel engine operating with a PCCI calibration, near the estimated EURO 6/Tier2 Bin5 NOx emission limits. The research activity is the result of a collaborative project between Istituto Motori and Centro Ricerche Fiat aimed to carry out an exhaustive analysis of the compression ratio (CR) influence on the performance of a LD diesel engine. Starting from a reference engine configuration the CR was reduced in two steps sequentially. Each CR value was characterized under PCCI operation mode and, under conventional diesel operating mode, at maximum torque. The exploration of the PCCI application in the NEDC operating area was performed prefixing limits on maximum fuel consumption, maximum pressure rise and maximum tolerable smoke. The main result was that no significant increment in PCCI application area reducing the CR was possible without overcoming the limits.