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Four 1998 Mitsubishi Carismas, two equipped with direct injection and two with port fuel injection engines, were tested in 20,100 km intervals to determine the effect of mileage accumulation cycle, engine type, fuel and lubricant on vehicle deposits and emissions, acceleration and driveability performance. The program showed that engine fuel system deposits, including specifically those on intake valves, combustion chambers and injectors are formed in higher amounts in the GDI engine than the PFI engine. The fuel additive used reduced injector deposits and combustion chamber deposits in the GDI, but had no significant effect on intake valve deposits, which are affected by crankcase oil formulation. In GDI vehicles, deposited engines were found to have increased hydrocarbon and carbon monoxide emissions and poorer fuel economy and acceleration, but lower particulate emissions.

Four 1998 Mitsubishi Carismas, two equipped with direct injection (GDI) and two with port fuel injection engines (PFI) were tested in a designed experiment to determine the effect of mileage accumulation cycle, engine type, fuel and lubricant type on engine wear and engine oil performance parameters. Fuel types were represented by an unadditised base fuel meeting EEC year 2000 specifications and the same base fuel plus synthetic deposit control additive packages. Crankcase oils were represented by two types (1) a 5W-30 API SJ/ILSAC GF-2 type engine oil and (2) a 10W-40 API SH/CF ACEA A3/ B3-96 engine oil. The program showed that specific selection of oil additive chemistry may reduce formation of intake valve deposits in GDI cars.. In general, G-DI engines produced more soot and more pentane insolubles and were found to be more prone to what appears to be soot induced wear than PFI engines.

Increasingly stringent vehicle emissions legislation is being introduced throughout the world, regulating the allowed levels of particulate matter emitted from vehicle tailpipes. The regulation may prove challenging for gasoline vehicles equipped with modern gasoline direct injection (GDI) technology, owing to their increased levels of particulate matter production. It is expected that gasoline particulate filters (GPFs) will soon be fitted to most vehicles sold in China and Europe, allowing for carbonaceous particulate matter to be effectively captured. However, GPFs will also capture and accumulate non-combustible inorganic ash within them, mainly derived from engine oil. Studies exist to demonstrate the impact of such ash on GPF and vehicle performance, but these commonly make use of accelerated ash loading methods, which themselves introduce significant variation.

The growing need for improved fuel economy is a global challenge due to continuously tightening environmental regulations targeting lower CO2 emission levels via reduced fuel consumption in vehicles. In order to reach these fuel efficiency targets, it necessitates improvements in vehicle transmission hardware components by applying advanced technologies in design, materials and surface treatments etc., as well as matching lubricant formulations with appropriate additive chemistry. Axle lubricants have a considerable impact on fuel economy. More importantly, they can be tailored to deliver maximum operational efficiency over specific or wide ranges of operating conditions. The proper lubricant technology with well-balanced chemistries can simultaneously realize both fuel economy and hardware protection, which are perceived to have a trade-off relationship.

In the auto industry, lightweight window designs are drawing more attention for improved gas mileage and reduced exhaust emission. Corning’s Gorilla® Glass used in laminate design enables more than 30% weight reduction compared to conventional soda-lime glass laminates. In addition, Gorilla® Glass hybrid laminates (which are a laminate construction of a thick soda-lime glass outer play, a middle polyvinyl butyral interlayer, and a thin Gorilla Glass inner ply) also show significantly improved toughness due to advanced ion-exchange technology that provides high-surface compression. However, the reduced mass also allows increased transmission of sound waves through the windshield into the vehicle cabin. A system-level measurement approach has always been employed to assess overall vehicle acoustic performance by measuring sound pressure levels (SPL) at the driver’s ears. The measured sound signals are usually a superimposition of a variety of noise sources and transmission paths.

Compositions in the mixed strontium/calcium feldspar ([Sr/Ca]O·Al2O3·2SiO2) - aluminum titanate (Al2O3·TiO2) system have been investigated as alternative materials for the diesel particulate filter (DPF) application. A key attribute of these compositions is their low coefficient of thermal expansion (CTE). Samples have been prepared with porosities of >50% having average pore sizes of between 12 and 16μm. The superior thermal shock resistance, increased resistance to ash attack, and high volumetric heat capacity of these materials, coupled with monolithic fabrication, provide certain advantages over currently available silicon carbide products. In addition, based on testing done so far aluminum titanate-based filters have demonstrated chemical durability and comparable pressure drop (both bare and catalyzed) to current, commercially available, silicon carbide products.

With the increasing use of modern, EGR-equipped, heavy-duty diesel engines and the use of lower sulfur and alternate fuels, such as biodiesel, lubricants are being exposed to a range of different compositions of acids. To complement the traditional detergent bases, todays lubricants have evolved to include a higher proportion of basic materials from amine-derived sources to aid in oxidation and soot control. This paper explores the impact of the different sources of acids, some of the issues they create and how they can be addressed, exemplified in a prototype CJ-4 lubricant formulation.

A new gas phase kinetic model using Westbrook's gas phase n-heptane model and Frenklach's soot model was constructed. This model was then used to predict the impact on PAH formation as an indices of soot formation on ethanol/diesel fuel blends. The results were then compared to soot levels measured by various researchers. The ignition delay characteristics of ethanol were validated against experimental results in the literature. In this paper the results of the model and the comparison with experimental results will be discussed along with implications on the method of incorporation of additives and alternative fuels.

Diesel Oxidation Catalyst in conjunction with large frontal area substrates is a key element in HDV Diesel emission control systems. This paper describes and reviews tests on a set of various Diesel Oxidation Catalyst configurations (for example cell densities), all with the same catalyst coating. The Diesel Oxidation Catalyst specimens were subjected to the European Stationary Cycle (ESC), the European Transient Cycle (ETC), and the US heavy duty Federal Test Procedure (US FTP). The focus was to study relative emissions, pressure drop, and light-off performance. All tests were conducted using the same Detroit Diesel Series 60 engine operating on ultra low sulfur diesel fuel. In addition to this, the exhaust was regulated so that the backpressure on the engine, upstream of the catalyst was also the same for all catalysts.

The next generation of engine oil under development has been formulated to maintain beneficial oil lubrication properties at increased engine operating temperatures, increased drain-oil intervals, and with the recirculation of exhaust gas back through the engine (EGR). These conditions result in the formation of degradation products from decomposed fuel, additives, and base oil. Decomposition products containing reactive sulfur can result in the corrosion of copper alloys. Sulfur-containing compounds currently used in these formulations can include zinc dithiophosphates (ZDP), molydithiophosphates, molydithiocarbamates, and molybdic acid/amine complexes, along with sulfur containing detergents and antioxidants. Interactions among these components and others in the formulation often determine the propensity of these formulations for corrosion. This paper will discuss the results of corrosion bench tests used to screen oil formulations for copper corrosion.

A new generation of fluid technology using novel diesel fuel detergent/dispersant chemistry provides a multitude of beneficial effects to the diesel engine, especially the latest model designs. In addition to improved injector, valve and combustion chamber deposit removal, the additive restores power, fuel economy, performance and emission levels1. Positive observations have also been documented along with improved performance concerning crankcase lube viscosity, soot loading and TBN retention. An even greater added benefit is the inherent capability of the fuel additive to deal with several EGR issues now prominent with the introduction of new engines. Recent research, reported herein, has uncovered the extensive efficacy of this chemistry for piston durability and neutralization of ring corrosion phenomena. All of the beneficial additive attributes are further enhanced with increased oxidative and thermal fuel stability and no loss of filterability.

Stringent emissions standards with 95+% conversion efficiency requirements call for advanced ceramic catalyst supports with thinner walls, higher cell density and optimum cell shape. The extrusion technology for cellular ceramics has also made significant progress which permits the manufacture of advanced catalyst supports. Similarly, modifications in cordierite chemistry and the manufacturing process have led to improved microstructure from coatability and thermal shock points of view. The design of these supports, however, requires a systems approach to balance both the performance and durability requirements. Indeed as the wall gets thinner, the contribution of washcoat becomes more significant in terms of thermal mass, heat transfer, thermal expansion, hydraulic diameter and structural stiffness - all of which have an impact on performance and durability. For example, the thinner the wall is, the better the light-off performance will be.

Motorcycle OEMs faced with stringent global fuel economy and emission regulations are being forced to develop new hardware and emissions control technologies to remain compliant. Motorcycle oils have become an enabling technology for the development of smaller, more efficient engines operating at higher power density. Many OEMs have therefore become reliant on lubricants to not only provide enhanced durability under more extreme operating conditions, but to also provide fuel economy benefits through reduced energy losses. Unlike passenger car oils that only lubricate the engine, motorcycle oils must lubricate both the engine and the drive train. These additional requirements place different performance demands versus a crankcase lubricant. The drive train includes highly loaded gears that are exposed to high pressures, in turn requiring higher levels of oil film strength and antiwear system durability.

This paper will review the field of diesel emission control with the intent of highlighting representative studies that illustrate the state-of-the-art. First, the author reviews general technology approaches for heavy and light duty applications. Given the emerging significance of ultrafines to health, and to emission control technologies, an overview of the significant developments in ultrafine particulate science is provided, followed by an assessment of filter technology. Regarding NOx control, SCR (selective catalytic reduction) and LNT (lean NOx traps) progress is described. Finally, system integration examples are provided. In general, progress is impressive and studies demonstrate that high-efficiency systems are within reach in all highway vehicle sectors. Engines are making impressive gains, and will increase the options for emission control.

This summary covers representative developments from 2008 in diesel regulations, engine technology, and NOx, particulate matter (PM), and hydrocarbon (HC) control. Europe is finalizing the Euro VI heavy-duty (HD) regulations for 2013 with the intent of technologically harmonizing with the US. A new particle number standard will be adopted. California is considering tightening the light-duty fleet average to US Tier 2 Bin 2 levels, and CO2 mandates are emerging in Europe for LD, and in the US for all vehicles. LD engine technology is focused on downsizing to deliver lower CO2 emissions, enabled by advances in boost and EGR (exhaust gas recirculation). Emerging concepts are shown for attaining Bin 2 emission levels. HD engines will make deNOx systems optional for even the tightest NOx standards, but deNOx systems enable much lower fuel consumption levels and will likely be used. NOx control is centered on SCR (selective catalytic reduction) for diverse applications.

This summary covers the developments from 2007 in diesel regulations, engine technology, and NOx and PM control. Regulatory developments are now focused on Europe, where heavy-duty regulations have been proposed for 2013. The regulations are similar in technology needs to US2010. Also, the European Commission proposed the first CO2 emission limits of 130 g/km, which are nearly at parity to the Japanese fuel economy standards. Engines are making very impressive progress, with clean combustion strategies in active development mainly for US light-duty application. Heavy-duty research engines are more focused on traditional approaches, and will provide numerous engine/aftertreatment options for hitting the tight US 2010 regulations. NOx control is centered on SCR (selective catalytic reduction) for diverse applications. Focus is on cold operation and system optimization. LNT (lean NOx traps) durability is quantified, and performance enhanced with a sulfur trap.

This summary covers the developments from 2006 in diesel regulations, engine combustion, and NOx and PM remediation. Regulatory developments are now focused on Europe, where light-duty Euro 5 and 6 regulations have been proposed for 2009 and 2014, respectively. The regulations are lass stringent than those in the US, but options exist for adopting European vehicles for the US market. Europe is just beginning to look at heavy-duty regulations for 2012 and beyond. Engines are making very impressive progress, with clean combustion strategies in active development mainly for US light-duty application. Heavy-duty research engines are more focused on traditional approaches, and will provide numerous engine/aftertreatment options for hitting the tight US 2010 regulations. NOx control is focusing on SCR (selective catalytic reduction) for diverse applications. Focus is on cold operation, durability, secondary emissions, and system optimization.

The paper summarizes the key developments in diesel emission control, generally for 2005. Regulatory targets for the next 10 years and projected advancements in engine technology are used to estimate future emission control needs. Recent NOx control developments on selective catalytic reduction (SCR), lean NOx traps (LNT) and lean NOx catalysts (LNC) are then summarized. Likewise, the paper covers important recent developments on diesel particulate filters (DPFs), summarizing regeneration strategies, new filter and catalyst materials, ash management, and PM measurement. Recent developments in diesel oxidation catalysts are also briefly summarized. Finally, the paper discusses examples of how it is all pulled together to meet the tightest future regulations.

Driven mainly by tightening of regulations, advance diesel emission control technologies are rapidly advancing. This paper will review the field with the intent of highlighting representative studies that illustrate the state-of-the-art. First, the author makes estimates of the emission control efficiency targets for heavy and light duty applications. Given the emerging significance of ultrafines to health, and to emission control technologies, an overview of the significant developments in ultrafine particulate science is provided, followed by an assessment of filter technology. Major deNOx catalyst developments, in addition to SCR and LNT progress is described. Finally, system integration examples are provided. In general, progress is impressive and studies have demonstrated that high-efficiency systems are within reach in all sectors highway vehicle sectors. Engines are making impressive gains, and will increase the options for emission control.

The characterization of the thermal and vibration environment of the exhaust systems of three modern day diesel engines, with displacements ranging from 1.9 liter to 12.7 liter, was carried out to support the development of exhaust after treatment components. Tri-axial accelerometer and in pipe thermocouple measurements were recorded at several locations along the exhaust systems during vehicle acceleration and steady driving conditions up to 70 mph. The vehicles were loaded to various gross weight configurations to provide a wide range of engine load conditions. Narrow band and octave band vibration power spectral densities are presented and conclusions are drawn as to the spectral content of the exhaust vibration environment and its distribution along the exhaust system. Temperature time histories during vehicle acceleration runs are likewise presented to indicate expected peak exhaust temperatures.