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The low temperature conditions that occur during high efficiency clean combustion (HECC) often lead to the formation of partially oxidized HC species such as aldehydes, ketones and carboxylic acids. Using the diesel fuels specified by the Fuels for Advanced Combustion Engines (FACE) working group, carbonyl species were collected from the exhaust of a light duty diesel engine operating under HECC conditions. High pressure liquid chromatography - mass spectrometry (LC-MS) was used to speciate carbonyls as large as C 9 . A relationship between carbonyl species formed in the exhaust and fuel composition and properties was determined. Data were collected at the optimum fuel efficiency point for a typical road load condition. Results of the carbonyl analysis showed changes in formaldehyde and acetaldehyde formation, formation of higher molecular weight carbonyls and the formation of aromatic carbonyls.

Lean NOx Trap (LNT) catalysts can effectively reduce NOx from lean engine exhaust. Significant research for LNTs in diesel engine applications has been performed and has led to commercialization of the technology. For lean gasoline engine applications, advanced direct injection engines have led to a renewed interest in the potential for lean gasoline vehicles and, thereby, a renewed demand for lean NOx control. To understand the gasoline-based reductant chemistry during regeneration, a BMW lean gasoline vehicle has been studied on a chassis dynamometer. Exhaust samples were collected and analyzed for key reductant species such as H₂, CO, NH₃, and hydrocarbons during transient drive cycles. The relation of the reductant species to LNT performance will be discussed. Furthermore, the challenges of NOx storage in the lean gasoline application are reviewed.

Advanced combustion regimes such as homogeneous charge compression ignition (HCCI) and premixed charge compression ignition (PCCI) offer benefits of reduced nitrogen oxides (NOX) and particulate matter (PM) emissions. However, these combustion strategies often generate higher carbon monoxide (CO) and hydrocarbon (HC) emissions. In addition, aldehydes and ketone emissions can increase in these modes. In this study, the engine-out emissions of a compression-ignition engine operating in a fuel reactivity-controlled PCCI combustion mode using in-cylinder blending of gasoline and diesel fuel have been characterized. The work was performed on a 1.9-liter, 4-cylinder diesel engine outfitted with a port fuel injection system to deliver gasoline to the engine. The engine was operated at 2300 rpm and 4.2 bar brake mean effective pressure (BMEP) with the ratio of gasoline-to-diesel fuel that gave the highest engine efficiency and lowest emissions.

In CFD (Computational Fluid Dynamics) verification of vehicle aerodynamics, detailed velocity measurements are required. The conventional 2D-PIV (Two Dimensional Particle Image Velocimetry) needs at least twice the number of operations to measure the three components of velocity ( u,v,w ), thus it is difficult to set up precise measurement positions. Furthermore, there are some areas where measurements are rendered impossible due to the relative position of the object and the optical system. That is why the acquisition of detailed velocity data around a vehicle has not yet been attained. In this study, a detailed velocity measurement was conducted using a 3D-PIV measurement system. The measurement target was a quarter scale SAE standard vehicle model. The wind tunnel system which was also designed for a quarter scale car model was utilized. It consisted of a moving belt and a boundary suction system.

A multi-objective optimization model using a piston behavior simulation for the prediction of NV, friction and scuffing was created. This model was used to optimize the piston skirt form, helping to enable well-balanced forms to be sought. Optimization calculations, involving extended analyses and numerous design variables, conventionally necessitate long calculation times in order to achieve adequate outcomes. Because of this, in the present project data was converted into functions in order to help enable the complex piston skirt form to be expressed using a small amount of coefficients. Using the limit values for manufacturability and the degree of contribution to the target functions, the scope of design variables was restricted, and the time necessary for the analysis was significantly reduced. This has helped to enable optimal solutions to be determined within a practical time frame.

We report a chemical sensing technology composed of engineered bioluminescent bacteria placed on an integrated microluminometer. The bacteria have been engineered to luminesce when the targeted compound is metabolized, while the microluminometer detects, processes, and then reports the magnitude of this optical signal. In this work we report our progress in the development of these biosensors and present data from our prototypes.

We report a chemical sensing technology composed of engineered bioluminescent bacteria placed on an integrated microluminometer. The bacteria have been engineered to luminesce when the targeted compound is metabolized, while the microluminometer detects, processes, and then reports the magnitude of this optical signal. In this work we report our progress in the development of these biosensors and present data from our early prototypes.

The widespread adoption of boosted, downsized SI engines has brought pre-ignition phenomena into greater focus, as the knock events resulting from pre-ignitions can cause significant hardware damage. Much attention has been given to understanding the causes of pre-ignition and identify lubricant or fuel properties and engine design and calibration considerations that impact its frequency. This helps to shift the pre-ignition limit to higher specific loads and allow further downsizing but does not fundamentally eliminate the problem. Real-time detection and mitigation of pre-ignition would thus be desirable to allow safe engine operation in pre-ignition-prone conditions. This study focuses on advancing the time of detection of pre-ignition in an engine cycle where it occurs.

Exhaust gas recirculation (EGR) cooler fouling has become a significant issue for compliance with nitrogen oxides (NOx) emissions standards. In order to better understand fouling mechanisms, eleven field-aged EGR coolers provided by seven different engine manufacturers were characterized using a suite of techniques. Microstructures were characterized using scanning electron microscopy (SEM) and optical microscopy following mounting the samples in epoxy and polishing. Optical microscopy was able to discern the location of hydrocarbons in the polished cross-sections. Chemical compositions were measured using thermal gravimetric analysis (TGA), differential thermal analysis (DTA), gas chromatography-mass spectrometry (GC-MS), x-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD). Mass per unit area along the length of the coolers was also measured.