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Dedicated EGR has shown promise for achieving high efficiency with low emissions [1]. For the present study, a 4-cylinder turbocharged GDI engine which was modified to a D-EGR configuration was used to investigate the impact of valve phasing and different injection strategies on the reformate production in the dedicated cylinder. Various levels of positive valve overlap were used in conjunction with different approaches for dedicated cylinder over fueling using PFI and DI fuel systems. Three speed-load combinations were studied, 2000 rpm 4 bar IMEPg, 2000 rpm 12 bar IMEPg, and 4000 rpm 12 bar IMEPg. The primary investigation was conducted to map out the dedicated cylinders' performance at the operating limits of intake and exhaust cam phasing. In this case, the limits were defined as conditions that yielded either no reformate benefit or led to instability in the dedicated cylinder.

Since product designs are defined and communicated using the language established by engineering drawing standards, the role of these standards and their impact on product quality is examined. This includes: 1. A historical review and analysis of the foundation upon which the engineering drawing standards in this country have been based. 2. The importance of good design and adequate design definition on drawings in a language which is widely recognized and understood. 3. The equal importance of dynamic constantly improving engineering drawing and design standards based on product experience and knowledge acquired in the solution of factory and in-service problems (as illustrated by a number of actual cases). 4. An assessment of the challenges of the 1980's and the advances expected to be made during this decade.

The Clean Air and Water Acts have dramatically impacted the way American manufacturing conducts its business. “End-of-pipe”: control of the more obvious pollutants resulting from production processes is now well established. What is less apparent is the impact of third generation environmental legislation on process operations, choice of materials and even choices among alternate production technologies. Pollution minimization at source becomes increasingly important as we become concerned with refractory materials which are toxic in small amounts and expensive or impossible to treat by conventional means. Environmental control is seen more and more as a multi-media effort reaching to the very heart of the factory, involving all aspects of the production process and having implications in the area of product design itself.

Automatic transmission fluid (ATF) performance is determined by the choice of lubricant basestocks and additives used to formulate the fluid. The lubricant basestocks employed set the fundamental low temperature capabilities and resistance to oxidation of the fluid. Over the last decade, ATF specifications issued by the major North American transmission builders have required significant improvements in low temperature fluidity and oxidation stability. These required improvements have begun to limit the number of basestocks capable of producing suitable fluids. The practical impact of this evolution is that API Group I basestocks are rapidly becoming incapable of producing the new generation of ATFs. Recently issued, and proposed, specifications will clearly continue this trend. Future ATF formulations may well be forced to move to API Group II, Group III and/or synthetic base fluids to meet these increasing performance requirements.

This work studies the complex interactions resulting from the application and control of Exhaust Gas Recirculation (EGR) on a production heavy-duty diesel engine system, and its effectiveness in reducing NOx emissions. The coupling between EGR, the Variable Geometry Turbocharger (VGT) and the EGR cooler critically affects boost pressure, air/fuel ratio (A/F), combustion efficiency and pumping work. It is shown that EGR provides an effective means for reducing flame temperatures and NOx emissions, particularly under low A/F ratio conditions. However, engine thermal efficiency tends to decrease with EGR as a result of decreasing indicated work and increasing pumping work. Combustion deterioration is predominant at higher load, low speed and low boost conditions, due to a significant decrease of A/F ratio with increasing EGR.

Water piston internal combustion engine is a very simple propulsive engine invented in the 1970's to be used in different applications. The water piston engine consists simply of L shape tube immersed in water where the water column inside the tube acts as a piston. In the present study, two propulsive units from this engine were compared. The two units are identical in their dimensions except the exit port where one is curved and the other one is sharp. The effect of this shape on the engine thrust, fuel consumption, power and number of effective firing was investigated. The effect of combustion chamber size on engine performance is also considered for the two units in this study.

Practical Experimental Stress Analysis (ESA) techniques are considered in terms of where they were, are now, and where they appear to be headed. The electrical resistance strain gage, with associated instrumentation, remains the overwhelming favorite when measurements are made at points. The impact of computer technology, primarily through software capabilities, has significantly enhanced data acquisition, presentations, and accuracy. Brittle coatings and variations of the photoelastic technique dominate the practical industrial scene when “full-field” stress information and understanding are of primary interest. Industrial case histories are included and illustrate present day thinking and technology.

Fibrous materials are often used to fill chambers in automotive silencers to achieve acoustic attenuation of air borne noise (especially above 200 Hz) in exhaust systems. It is clear that one of the major determinants of the acoustic performance of an absorptive silencer is the amount of fibrous material in the silencer [1]. However, there is little published data as to the impact upon acoustic performance of fiber packing density variations [2] within a silencer chamber In this study, cylindrical silencers with a straight through perforated tube have been used to experimentally study the impact of large density variations and voids, in both the radial and axial directions, upon the acoustic performance of a silencer. The acoustic transmission loss in a no-flow apparatus was the test measurement employed to determine acoustic performance.

When an airline finds itself in trouble with an engine because of high cost or poor reliability, or both, decisions frequently must be made long before a complete picture is available to the decision makers. Experience and judgment play a major role in selecting the course of corrective action. This paper reviews these difficult decisions in a specific case history. The results of those decisions are analyzed quantitatively and the significance of the results discussed qualitatively. A relationship is then drawn between the operators’ experiences and the design criteria established by the engine manufacturer in the design of new engines.

Gasoline is composed of hundreds of components. The fuel properties can present a wide range of variation, depending on the formulation. Commercial fuel specifications differ from country to country, based on the features of each market. Also, fuels for some specific engine applications can differ widely from commercial fuels. For the next decades it is expected that the fossil fuels and bio-fuels usage in internal combustion engines remains to be the main source for vehicular propulsion. This justifies the intense worldwide research and development to comply with the challenges of increasing efficiency and emissions reduction. In this context the fuel can play an important role, mainly when there is the possibility to optimize fuel formulation, engine design and engine calibration for the desired application.

Toyota and BP have performed a collaborative study to understand the impact of fuel composition on the combustion and emissions of a prototype 1.8L lean boosted engine. The fuel matrix was designed to understand better the impact of a range of fuel properties on fundamental combustion characteristics including thermal efficiency, combustion duration, exhaust emissions and extension of lean limit. Most of the fuels in the test matrix were in the RON range of 96 - 102, although ethanol and other high octane components were used in some fuels to increase RON to the range 104 - 108. The oxygen content ranged from 2 - 28%, and constituents included biocomponents, combustion improving additives and novel blend components. Performance and emissions tests were conducted over a range of engine operating conditions. Thermal efficiency was mapped at stoichiometric and lean conditions, and the limit of lean combustion was established for different fuels.

Ethanol has long been a fuel of considerable interest for use as an automotive fuel in spark ignition (SI) internal combustion engines. In recent years, concerns over oil supplies, sustainability and geopolitical factors have lead multiple jurisdictions to mandate the blending of ethanol into standard gasoline. The impact of blend ethanol content on gaseous emissions has been widely studied; particulate matter emissions have received somewhat less attention, despite these emissions being regulated in the USA. Currently, in the EU particulate matter emissions from SI engines are partially regulated - only vehicles featuring direct injection SI engines are subject to emissions limits. A range of experiments was conducted to determine the impact of fuel ethanol content on the emissions of solid pollutants from Euro 5 passenger cars.

Gasoline compression ignition using a single gasoline-type fuel has been shown as a method to achieve low-temperature combustion with low engine-out NOx and soot emissions and high indicated thermal efficiency. However, key technical barriers to achieving low temperature combustion on multi-cylinder engines include the air handling system (limited amount of exhaust gas recirculation) as well as mechanical engine limitations (e.g. peak pressure rise rate). In light of these limitations, high temperature combustion with reduced amounts of exhaust gas recirculation appears more practical. Furthermore, for high temperature Gasoline compression ignition, an effective aftertreatment system allows high thermal efficiency with low tailpipe-out emissions. In this work, experimental testing was conducted on a 12.4 L multi-cylinder heavy-duty diesel engine operating with high temperature gasoline compression ignition combustion using EEE gasoline.

Fuel tracer-based planar laser-induced fluorescence is used to investigate the vaporization and mixing behavior of pilot injections for variations in pilot mass of 1-4 mg, and for two injection pressures, two near-TDC ambient temperatures, and two swirl ratios. The fluorescent tracer employed, 1-methylnaphthalene, permits a mixture of the diesel primary reference fuels, n-hexadecane and heptamethylnonane, to be used as the base fuel. With a near-TDC injection timing of −15°CA, pilot injection fuel is found to penetrate to the bowl rim wall for even the smallest injection quantity, where it rapidly forms fuel-lean mixture. With increased pilot mass, there is greater penetration and fuel-rich mixtures persist well beyond the expected pilot ignition delay period. Significant jet-to-jet variations in fuel distribution due to differences in the individual jet trajectories (included angle) are also observed.

An experimental study of particulate matter and volatile organic compounds (VOCs) emissions was conducted on a direct injection gasoline (DIG) engine and a port fuel injection (PFI) engine which both were produced by Chinese original equipment manufacturers (OEMs) to investigate the impact of fuel properties from Chinese market on particulate and VOCs emissions from modern gasoline vehicles. The study in this paper is just the first step of the work which is to investigate the impact of gasoline fuel properties and light duty vehicle technologies on the primary and secondary emissions, which are the sources of particulate matter 2.5 (PM2.5) in the atmosphere in China. It is expected through the whole work to provide some suggestions and guidelines on how to improve air quality and mediate severe haze pollution in China through fuel quality control and vehicle technology advances.

Fuel properties impact the engine-out emission directly. For some geographic regions where diesel engines can meet emission regulations without aftertreatment, the change of fuel properties will lead to final tailpipe emission variation. Aftertreatment systems such as Diesel Particulate Filter (DPF) and Selective Catalytic Reduction (SCR) are required for diesel engines to meet stringent regulations. These regulations include off-road Tier 4 Final emission regulations in the USA or the corresponding Stage IV emission regulations in Europe. As an engine with an aftertreatment system, the change of fuel properties will also affect the system conversion efficiency and regeneration cycle. Previous research works focus on prediction of engine-out emission, and many are based on chemical reactions. Due to the complex mixing, pyrolysis and reaction process in heterogeneous combustion, it is not cost-effective to find a general model to predict emission shifting due to fuel variation.

Studies on cold flow performance have focused on the n-alkane wax precipitating from diesel fuel and their interaction with additives. Little attention has been paid to the solvent system of the fuel. There have been significant changes in the fuel solvent system, due to changes in refining processes and the use of first and second generation biofuels, as well as other components such as GTL. Understanding the extent of the impact of the fuel solvent system change, if and how the change effects wax precipitation, and whether the change influences additive wax interactions, will ultimately enable the optimisation of diesel fuel cold flow performance. This paper first describes a method to characterise diesel fuel solvency. The method is applied to sets of fuels to evaluate the changes in fuel composition over time. A method to replicate the variation in the fuel solvent system is described. The impact of changes in the solvent systems on cold flow properties is considered.

With the advent of stricter vehicle emission standards, the improvement of three way catalyst performance and durability remains a pressing issue. A critical consideration in catalyst design is the potential for variations in fuel sulfur levels to have a significant impact on the ability to reach TLEV, LEV, and ULEV emission levels. As a result, a better understanding of the role of PGM composition in the interplay between thermal durability and sulfur tolerance is required. Three way catalysts representative of standard Pd-only, Pd/Rh and Pt/Rh formulations were studied over a variety of aging and evaluation conditions. The parameters investigated included aging temperature, air fuel ratio and sulfur level. Evaluations were performed on a 1994 TLEV vehicle using different sulfur level fuels. The effect of PGM loading was also included within the study.

Federal Test Procedure (FTP) emissions were measured on a 2009 4 cylinder 2.4L Malibu PZEV vehicle with 10 and 30ppm sulfur fuel while varying the PGM (Platinum Group Metals) of the close-coupled and underfloor converters. Base CARB PH-III certification fuel was used. Three consecutive FTPs were used to measure the impact of fuel sulfur and catalyst PGM loading combinations. In general, reducing fuel sulfur and increasing catalyst PGM loadings, decrease FTP emissions. Increasing Pd concentrations can mitigate the impact of higher fuel sulfur concentrations. The results also suggest that a 50% reduction in PGM can be achieved with a reduction in fuel sulfur from 30 to 10 ppm. On average, NMHC, CO and NOx emissions were reduced by 12, 49 and 64%, respectively with the 10 ppm sulfur fuel. In addition, HC and NOx vehicle emission variability were reduced by 74 and 57% with the 10 ppm sulfur fuel.

Gasoline direct injection (GDI) engine technology is now widely used due to its high fuel efficiency and low CO2 emissions. However, particulate emissions pose one challenge to GDI technology, particularly in the presence of fuel injector deposits. In this paper, a 4-cylinder turbocharged GDI engine in the Chinese market was selected and operated at 2000rpm and 3bar BMEP condition for 55 hours to accumulate injector deposits. The engine spark timing, cylinder pressure, combustion duration, brake specific fuel consumption (BSFC), gaseous pollutants which include total hydro carbon (THC), NOx (NO and NO2) and carbon dioxide (CO), and particulate emissions were measured before and after the injector fouling test at eight different operating conditions. Test results indicated that mild injector fouling can result in an effect on engine combustion and emissions despite a small change in injector flow rate and pulse width.