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Controlled auto ignition combustion mode has become a topic of major interest in recent years, mainly due to its potential in achieving high thermal efficiencies combined with significant reductions in NOx and soot emissions. However, expanding the controlled operation over a wide range of speeds and loads is a significant challenge, which must be addressed to achieve commercial success. Control analysis to date has been done by developing models which are engine specific, such models often rely on extensive parameters which are to be experimentally identified. Moreover, these models were valid only for a narrow operating range. In this paper, a detailed mathematical model of an HCCI engine, which is fuel flexible and valid for a transitions in engine speed, is developed based on ideal gas laws and basic thermodynamics and conservation principles.

Current emission control systems utilize a catalytic converter employing a three-way catalyst (TWC), composed of a mixture of noble metals to minimize the three main pollutant classes of NOx, CO, and HC. The TWC is most efficient when the air-to-fuel ratio (A/F) is at stoichiometry (i.e. A/F ≈ 14.7). The stoichiometric set-point region is maintained by the use of oxygen sensors composed of the solid-electrolyte yttria stabilized zirconia (YSZ) in an electronic feedback loop. As combustion gets leaner a different exhaust sensor can be utilized to give a measure of the level of pollutants. A NOx sensor is an alternative for an oxygen sensor that can be used for feedback control of engine combustion or exhaust NOx traps. A solid electrolyte disk composed of YSZ having two Pt electrodes with one being covered by a microporous zeolite material was tested as a sensor for combustion produced gases such as NO and NO2 in the presence of O2.

Filtration of diesel and gasoline fuel in automotive applications is affected by many external and internal parameters, e.g. vibration, temperature, pressure, flow pulsation, and engine start-stop. Current test procedures for automotive fuel filters, proposed by most of the researchers and organizations including Society for Automotive Engineers (SAE) and International Organization for Standardization (ISO), do not apply the previously mentioned real-world-conditions. These operating conditions, which are typical for an automotive fueling system, have a significant effect on fuel filtration and need to be considered for the accurate assessment of the filter. This requires the development of improved testing procedures that will simulate the operating conditions in a fuel system as encountered in the real world.

The information provided by the in-cylinder pressure signal is of great importance for modern engine management systems. The obtained information is implemented to improve the control and diagnostics of the combustion process in order to meet the stringent emission regulations and to improve vehicle reliability and drivability. The work presented in this paper covers the experimental study and proposes a comprehensive and practical solution for the estimation of the in-cylinder pressure from the crankshaft speed fluctuation. Also, the paper emphasizes the feasibility and practicality aspects of the estimation techniques, for the real-time online application. In this study an engine dynamics model based estimation method is proposed. A discrete-time transformed form of a rigid-body crankshaft dynamics model is constructed based on the kinetic energy theorem, as the basis expression for total torque estimation.

In recent years, the increasing interest and requirements for improved engine diagnostics and control has led to the implementation of several different sensing and signal processing technologies. In order to optimize the performance and emission of an engine, detailed and specified knowledge of the combustion process inside the engine cylinder is required. In that sense, the torque generated by each combustion event in an IC engine is one of the most important variables related to the combustion process and engine performance. This paper introduces torque estimation techniques in the real-time basis for engine control applications using the measurement of crankshaft speed variation. The torque estimation scheme presented in this paper consists of two entirely different approaches, “Stochastic Analysis” and “Frequency Analysis”.

The stochastic Fault Detection and Isolation (FDI) algorithm, known as the statistical local approach, is applied in a model-based framework to the diagnosis of component faults in the air-intake system of an automotive engine. The FDI scheme is first presented as a general methodology that permits the detection of faults in complex nonlinear systems without the need for building inverse models or numerous observers. Although sensor and actuator faults can be detected by this FDI methodology, component faults are generally more difficult to diagnose. Hence, this paper focuses on the detection and isolation of component faults for which the local approach is especially suitable. The challenge is to provide robust on-board diagnostics regardless of the inherent nonlinearities in a system and the random noise present.

Stringent emissions regulations set forth by the Environmental Protection Agency has forced the automotive industry in the United States to seek a low cost and reliable solution to meet these regulations. Homogeneous Charge Compression Ignition (HCCI) is one of the potential answers to the problem. The HCCI combustion process combines the benefits of the two main Internal Combustion Engines (ICE) technologies, Spark Ignition (SI) and Compression Ignition Direct Injected (CIDI). The HCCI combustion process is building on the advantages of each technology while avoiding the disadvantages. One of the hurdles preventing the successful application of an HCCI engine to the main automotive market is how to supply the required heat, needed for establishing HCCI in an engine. In this researcha Thermal Barrier Coating (TBC) is designed to harness the energy normally wasted by the engine through the engine's exhaust and cooling systems.

The paper presents a possible concept design for integration of individual wheel AC motors into Oshkosh Truck Corporation's InDependent Suspension. A new axle concept design (including drive line and CV-joint) is presented with a new AC induction motor concept. Both concepts are able to match 100% the sever-heavy duty requirements in a large area of advanced on and off road traction applications. Concepts are suitable for modularity in a multi-axle (2-6) All-Wheel Drive, All Steer configuration vehicle.