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The finite nature and instability of fossil fuel supply has led to an increasing and enduring investigation demand of alternative and regenerative fuels. An investigation program is carried out to explore the potential of tailor made fuels to reduce engine-out emissions while maintaining engine efficiency and an acceptable noise level. In this paper, fundamental results of the Diesel engine relevant combustion are presented. To enable optimum engine performance a range of different reference fuels have been investigated. The fundamental effects of different physical and chemical properties on emission formation and engine performance are investigated using a thermodynamic diesel single cylinder research engine and an optically-accessible combustion vessel. Depending on the chain length and molecular structure, fuel compounds vary in cetane number, boiling temperature etc. Therefore, different hydrocarbons including n-heptane, n-dodecane, and l-decanol were investigated.

Initial results are presented for the production of hydrogen from waste lubricating oil using a chemical looping reforming (CLR) process. The development of flexible and sustainable sources of hydrogen will be required to facilitate a "hydrogen economy." The novel CLR process presented in this paper has an advantage over hydrogen production from conventional steam reforming because CLR can use complex, low value, waste oils. Also, because the process is scalable to small and medium size, hydrogen can be produced close to where it is required, minimizing transport costs. Waste lubricating oil typically contains 13-14% weight of hydrogen, which through the steam reforming process could produce a syngas containing around 75 vol% H₂, representing over 40 wt% of the fuel. The waste oil was converted to a hydrogen-rich syngas in a packed bed reactor, using a Ni/ Al₂O₃ catalyst as the oxygen transfer material (OTM).

Future synthetic diesel fuels will likely involve mixtures of straight and branched alkanes, possibly with aromatic additives to improve lubricity and durability. To simulate these future fuels, this study examined the combustion characteristics of binary mixtures of 50%, 70%, and 90% isododecane in hexadecane, and of 50%, 70%, and 80% toluene in hexadecane using a single-cylinder research diesel engine with variable injection timing. These binary blends were also compared to operation with commercial petroleum diesel fuel, military petroleum jet fuel, and five current synthetic Fischer-Tropsch diesel and jet fuels. The synthetic diesel and jet fuels showed reasonable similarity with many of the combustion metrics to mid-range blends of isododecane in hexadecane. Stable diesel combustion was possible even with the 80% toluene and 90% isododecane blends; in fact, operation with 100% isododecane was achieved, although with significantly advanced injection timing.

The paper discusses the concept, specification and performance of a new, dedicated range extender engine for plug-in series hybrid vehicles conceived and designed by Lotus Engineering. This has been undertaken as part of a consortium project called Limo Green, part-funded by the UK government. The Lotus Range Extender engine has been conceived from the outset specifically as an engine for a plug-in series hybrid vehicle, therefore being free of some of the constraints placed on engines which have to mate to conventional, stepped mechanical transmissions. The paper starts by defining the philosophical difference between an engine for range extension and an engine for a full series hybrid vehicle, a distinction which is important with regard to how much power each type must produce. As part of this, the advantages of the sparkignition engine over the diesel are outlined.

Lithium-ion (Li-ion) batteries are becoming widely used high-energy sources and a replacement of the Nickel Metal Hydride batteries in electric vehicles (EV), hybrid electric vehicles (HEV) and plug-in hybrid electric vehicles (PHEV). Because of their light weight and high energy density, Li-ion cells can significantly reduce the weight and volume of the battery packs for EVs, HEVs and PHEVs. Some materials in the Li-ion cells have low thermal stabilities and they may become thermally unstable when their working temperature becomes higher than the upper limit of allowed operating temperature range. Thus, the cell working temperature has a significant impact on the life of Li-ion batteries. A proper control of the cell working temperature is crucial to the safety of the battery system and improving the battery life. This paper outlines an approach for the thermal analysis of Li-ion battery cells and modules.

This study aims to identify the factors that control particulate matter (PM) formation and size distribution in direct-injection spark-ignition (DISI) engines. The test engine used for this research was a 1.6 litre, wall-guided DISI, turbocharged, intercooled, in-line 4 cylinder, Euro IV engine. The exhaust sampling point was before the catalytic converter, i.e. engine-out emissions were measured. The first part of this paper investigates the characteristics of PM number and size distribution of DISI and throttle body injected (TBI) engines. The second part investigates the effect of combustion characteristics of DISI engines on the number of 5nm and 10nm (nucleation) and 200nm (accumulation) PM. A statistical analysis of the coefficient of variance (COV) of the maximum rate of pressure rise (RPmax) over 100 cycles was performed against the COV of 5nm, 10nm and 200nm total particle number.

To meet increasingly stringent diesel exhaust emissions requirements, original equipment manufacturers (OEMs) have introduced common rail fuel injection systems that develop pressures of up to 2000 bar (30,000 psi). In addition, fuel delivery schemes have become more complicated, often involving multiple injections per cycle. Containing higher pressures and allowing for precise metering of fuel requires very tight tolerances within the injector. These changes have made injectors more sensitive to fuel particulate contamination. Recently, problems caused by internal diesel injector deposits have been widely reported. In this paper, the results of an investigation into the chemical nature and probable sources of these deposits are discussed. Using an array of techniques, internal deposits were analyzed from on a number of sticking injectors from the field and from OEM test stands in North America.

Wet clutches are important components used in the transmission and drive trains of many modern vehicles. The clutches transfer torque via the friction between a number of friction discs and the friction characteristics is therefore of great importance for the overall behavior of the vehicles. The friction characteristics is governed by a number of parameters such as lubricant base oil and additives, type and permeability of the friction material and temperature and surface roughness of the interacting surfaces. The permeability is considered to influence time of engagement and supply the sliding interface with lubricant and additives during engagement. In this work, a permeability measurement method suitable for wet clutch friction materials is thus used to measure the permeability of friction materials of different types; sintered bronze and paper based materials.

Nowadays, developing of effective camless engine systems, allowing Variable Valve Actuation (VVA), is one of the fundamental automotive challenge to increase engine power, reduce fuel consumption and pollutant emissions, as well as improve the engine efficiency significantly. Electromechanical devices based on double electromagnets have shown to be a promising solution to actuate engine valves during normal engine cycle due to their efficient working principle. Conversely, this solution requires special care at the key-on engine for the first valve lift, when the valve must be shifted from the middle equilibrium position to the closing one with limited coil currents and power requirements as well. Despite the central role of the first catching problem, few attempts have been done into the existing literature to tackle it systematically.

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.

An infrared laser absorption technique has been developed to measure in-cylinder concentrations of CO in an optical, automotive HCCI engine. The diagnostic employs a distributed-feedback, tunable diode laser selected to emit light at the R15 line of the first overtone of CO near 2.3 μm. The collimated laser beam makes multiple passes through the cylinder to increase its path length and its sampling volume. High-frequency modulation of the laser output (wavelength modulation spectroscopy) further enhances the signal-to-noise ratio and detection limits of CO. The diagnostic has been tested in the motored and fired engine, exhibiting better than 200-ppm sensitivity for 50-cycle ensemble-average values of CO concentration with 1-ms time resolution. Fired results demonstrate the ability of the diagnostic to quantify CO production during negative valve overlap (NVO) for a range of fueling conditions.

Prior technical work by various OEMs and lubricant formulators has identified lubricant-derived phosphorus as a key element capable of significantly reducing the efficiency of modern emissions control systems of gasoline-powered vehicles ( 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ). However, measuring the exact magnitude of the detriment is not simple or straightforward exercise due to the many other sources of variation which occur as a vehicle is driven and the catalyst is aged ( 1 ). This paper, the second one in the series of publications, examines quantitative sets of results generated using various vehicle and exhaust catalyst testing methodologies designed to follow the path of lubricant-derived phosphorous transfer from oil sump to exhaust catalytic systems ( 1 ).

Modern diesel Fuel Injection Equipment (FIE) systems are susceptible to the formation of a variety of deposits. These can occur in different locations, e.g. in nozzle spray-holes and inside the injector body. The problems associated with deposits are increasing and are seen in both Passenger Car (PC) and Heavy Duty (HD) vehicles. Mechanisms responsible for the formation of these deposits are not limited to one particular type. This paper reviews FIE deposits developed in modern PC and HD engines using a variety of bench engine testing and field trials. Euro 4/ IV and Euro 5/V engines were selected for this programme. The fuels used ranged from fossil only to distillate fuels containing up to 10% Fatty Acid Methyl Ester (FAME) and then treated with additives to overcome the formation of FIE deposits.

The aim of the paper is the comparison of the injection process with different fuels, i.e. a standard diesel fuel and a pure biodiesel. Multiphase cavitating flows inside diesel nozzles are analyzed by means of unsteady CFD simulations using a two-fluid approach with consideration of bubble dynamics, on moving grids from needle opening to closure. Two five-hole nozzles with cylindrical and conical holes are studied and their behaviors are discussed taking into account the different properties of the two fuels. Extent of cavitation regions is not much affected by the fuel type. Biodiesel leads to significantly higher mass flow only if the nozzle design induces significant cavitation which extends up to the outlet section and if the injector needle is at high lift. If the internal hole shaping is able to suppress cavitation, the stabilized mass flows are very similar with both fuels.

Existing gasoline DI injection equipment has been modified to generate single hole pulsed gas jets. Injection experiments have been performed at combinations of 3 different pressure ratios (2 of which supercritical) respectively 3 different hole geometries (i.e. length to diameter ratios). Injection was into a pressure chamber with optical access. Injection pressures and injector hole geometry were selected to be representative of current and near-future DI natural gas engines. Each injector hole design has been characterized by measuring its discharge coefficient for different Re-levels. Transient jets produced by these injectors have been visualized using planar laser sheet Mie scattering (PLMS). For this the injected gas was seeded with small oil droplets. The corresponding flow field was measured using particle image velocimetry (PIV) laser diagnostics.

Simultaneous crank-angle-resolved measurements of gasoline concentration and gas temperature were made with two-color mid-infrared (mid-IR) laser absorption in a production spark-ignition engine (Nissan MR20DE, 2.0L, 4 cyl, MPI with premium gasoline). The mid-IR light was coupled into and out of the cylinder using fiber optics incorporated into a modified spark plug. The absorption line-of-sight was a 5.3 mm optical path located closely adjacent to the ignition spark providing spatially resolved absorption. Two sensor wavelengths were selected in the strong bands associated with the carbon-hydrogen (C-H) stretching vibration near 3.4 μm, which have an absorption ratio that is strongly temperature dependent. Fuel concentration and temperature were determined simultaneously from the absorption at these two wavelengths.

This study investigates the impact of mid-high biodiesel blends on the criteria and PAH emissions from a modern pick-up diesel vehicle. The vehicle was a Euro 4 (category N1, subclass III) compliant common-rail light-duty goods pick-up truck fitted with a diesel oxidation catalyst. Emission and fuel consumption measurements were performed on a chassis dynamometer equipped with CVS, following the European regulations. All measurements were conducted over the certification New European Driving Cycle (NEDC) and the real traffic-based Artemis driving cycles. Aiming to evaluate the fuel impact on emissions, a soy-based biodiesel, a palm-based biodiesel, and an oxidized biodiesel obtained from used frying oils were blended with a typical automotive ultra-low-sulfur diesel at proportions of 30, 50 and 80% by volume. The experimental results revealed that CO₂ emissions and fuel consumption exhibited an increase with biodiesel over all driving conditions.

Conventional diesel fuel has been in the market for decades and used successfully to run diesel engines of all sizes in many applications. In order to reduce emissions and to foster energy source diversity, new fuels such as alternative and renewable, as well as new fuel formulations have entered the market. These include biodiesel, gas-to-liquid, and alternative formulations by states such as California. Performance variations in fuel economy, emissions, and compatibility for these fuels have been evaluated and debated. In some cases contradictory views have surfaced. “Sustainable”, “Renewable”, and “Clean” designations have been interchanged. Adding to the confusion, results from one fuel in one type of engine such as an older heavy-duty engine, is at times compared to that of another type such as a modern light-duty. This study was an attempt to compare the performance of several fuels in an identical environment, using the same engine, for direct comparison.

Turbulent Jet Ignition is an advanced spark-initiated pre-chamber combustion system for an otherwise standard spark ignition engine found in current on-road vehicles. This next-generation pre-chamber design simply replaces the spark plug in a conventional spark ignition engine. Turbulent Jet Ignition enables very fast burn rates due to the ignition system producing multiple, widely distributed ignition sites, which consume the main charge rapidly. This high energy ignition system results from the partially combusted (reacting) pre-chamber products initiating main chamber combustion. The fast burn rates allow for increased levels of dilution (lean burn and/or EGR) when compared to conventional spark ignition combustion, with dilution levels being comparable to other low temperature combustion technologies (HCCI) without the complex control drawbacks.

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.