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Inert injection is an often-used technique to reduce NOx emissions from engines. Here the effects of a new Mitsubishi water injection system for a direct injection (DI) Diesel engine on exhaust emissions are examined. Stoichiometric flame temperature correlations of thermal NOx emissions for conventional gas turbine combustors provide an activation energy to form NO of approximately 135 kcal/g-mol, the value for the Zeldovich mechanism with O/O2 equilibrium. Two theoretical limiting temperatures determined to bracket NOx emissions data for gas turbines are computed for the Diesel engine considered here. At low water to fuel ratios, the reductions of NOx for the DI Diesel engine are less than predicted for uniform distribution of an inert throughout the charge, but as the water to fuel ratio is increased the reductions are bounded successfully by the limiting temperatures.

Experimental studies of fuel utilisation during the early stages of engine warm-up after cold-starts are reported. The investigation has been carried out on a 1.81, 4 cylinder spark-ignition engine with port electronic fuel injection. The relationship between fuel supplied and fuel accounted for by the analysis of exhaust gas composition shows that a significant mass of fuel supplied is temporarily stored or permanently lost. An interpretation of data is made which allows time-dependent variations of these to be separately resolved and estimates of fuel quantities made. The data covers a range of cold-start conditions down to -5°C at which, on a per cylinder basis, fuel stored peaks typically at around 0.75g and a total of 1g is returned over 100 seconds of engine running. Fuel lost past the piston typically accounts for 2g over 200 to 300 seconds of running.

On the whole, the assessment criteria leading to the selection of liquefied natural gas (LNG) as an alternate fuel have been fairly well developed. However, the technology needs have not been adequately addressed in many instances resulting in demonstration projects less successful than anticipated. Because LNG technology is more complex than that of conventional fuels such as gasoline and diesel, and because LNG as a transportation fuel is in the early stages of implementation, the technology needs must be very carefully addressed. This paper presents an overview of the design issues considered important to LNG fueling in ground transportation.

Ford Motor Company has introduced its dedicated Natural Gas Vehicle (NGV) trucks as mid-year 1997 offerings to complement its dedicated Crown Victoria and bi-fuel Qualified Vehicle Modifier (QVM) product line-up. The 5.4L F-250 full-size pick-up truck and the 5.4L E-250/E-350 full-size vans are production vehicles maintaining Original Equipment Manufacturer (OEM) quality and warranty while complying with all applicable corporate, federal and state requirements. Both trucks are the first OEM vehicles to certify at the Super Ultra Low Emission Vehicle (SULEV) California medium-duty vehicle standard, the Federal Ultra Low Emission Vehicle (ULEV) standard, and the Federal Inherently Low Emission Vehicle (ILEV) emission standard. The use of natural gas (NG) as a vehicle fuel required unique hardware changes in the areas of fuel storage, fuel metering, and the emission control system.

A group of GM C-2500 heavy-duty and GM C-1500 light-duty trucks were modified to bi-fuel compressed natural gas (CNG)/gasoline and liquefied petroleum gas (LPG)/gasoline vehicles. The fuel management systems used for different model year vehicles were introduced. The Alternative Fuel Technology (AFT) System used for 1997 GM C-2500 trucks is discussed in detail. AFT is an automatic switching bi-fuel system which is able to control fuel flow rate, spark timing, and EGR, and perform On-Board Diagnostics (OBD-II). The exhaust emissions of carbon monoxide (CO), total hydrocarbon (HC) and oxides of nitrogen (NOx) were measured using dilute sampling techniques. The vehicles tested were operated on a chassis dynamometer and run on the Federal Test Procedure (FTP) Urban Schedule.

This paper deals with the effects on diesel engine combustion and emissions of carbon dioxide and water vapour the two main constituents of EGR. It concludes the work covered in Parts 1, 2, and 3 of this series of papers. A comparison is presented of the different effects that each of these constituents has on combustion and emissions. The comparison showed that the dilution effect was the most significant one. Furthermore, the dilution effect for carbon dioxide is higher than that for water vapour because EGR has roughly twice as much carbon dioxide than water vapour. On the other hand, the water vapour had a higher thermal effect in comparison to that of carbon dioxide due to the higher specific heat capacity of water vapour. The chemical effect of carbon dioxide was, generally, higher than that of water vapour.

Alternative fuels are being evaluated in automotive applications in both commercial and government fleets in an effort to reduce emissions and United States dependence on diesel fuel. Vehicles and equipment have been operated using 100 percent biodiesel and various blends of biodiesel and diesel fuel in a variety of applications, including farming equipment and transit buses. This government study investigates the compatibility of four base fuels and six blends with elastomer and metallic components commonly found in fuel systems. The physical properties of the elastomers were measured according to American Society of Testing and Materials (ASTM) D 471, “Standard Test Method for Rubber Property-Effect of Liquids,” and ASTM D 412, “Standard Test Methods for Rubber Properties in Tension.” These evaluations were performed at 51.7°C for 0, 22, 70, and 694 hours. Tensile strength, hardness, swell, and elongation were determined for all specimens.

Raytheon E-Systems has developed and implemented an Individual Aircraft Tracking Program (IATP) that forms one element of a comprehensive Aircraft Structural Integrity Program (ASIP). This program aims to ensure the long-term structural integrity and continued airworthiness of a broad portion of the Federal Aviation Administration (FAA) Flight Inspection Fleet of aircraft. Specifically, six Learjet Model 60 and three Canadair Challenger CL601-3R aircraft are modified by Raytheon E-Systems to perform the Flight Inspection role for the FAA. Flight Inspection mission profiles are characterized by extensive operation below 2000 feet MSL (mean sea level). This low level, structurally harsh environment contrasts dramatically with typical corporate jet operational environments.

We have studied the fuel behavior in Port-injection gasoline engines as the following: 1. We have developed a 100%-sampling quantitative analysis method where fuel is sealed up in the intake port and cylinder at a specific point during firing operation, using an engine with intake and exhaust valves that are opened and closed by electronic control. 2. As a result of our analysis of steady and transient state characteristics of fuel behavior using this method, it was verified that the amount of wall-wetting fuel in the port and cylinder is apparently different before and after the warm-up process. As for transient fuel behavior, a delay in fuel transfer has been acknowledged in the amount of wall-wetting fuel not only in the port but also in the cylinder. Different from the existing indirect analysis, this method enables direct measurement of fuel behavior even during the actual firing operation.

A study was conducted to reduce unburned oil fractions in diesel particulate matter (PM) by improving oil consumption. A method utilizing radioisotope 14C was developed to measure the unburned oil fractions separately for the four paths by which oil is consumed: valve stem seals, piston rings, PCV system, turbocharger. The conversion ratio of oil consumption to PM was calculated by comparing the unburned oil emission rates with oil consumption rates, which were obtained by the use of the 35S tracer method. The result in an experimental diesel engine shows the highest conversion ratio for the oil leaking through the valve stem seals. The modifications to the engine were thereby focused on reducing the leakage of the stem seals. This stem seal modification, along with piston ring improvements, reduced oil consumption, resulting in the unburned oil fractions in PM being effectively reduced.

Engine calibrations are inexpensive methods for reducing exhaust emissions since only software modifications are required. The California Air Resources Board staff conducted a test program to investigate the effectiveness of engine calibration techniques to reduce the newly regulated aggressive driving exhaust emissions or “off-cycle” emissions. Consisting of stoichiometric and rich “bias” calibration, these engine calibration techniques were applied to fourteen late-model vehicles. The engine calibration techniques reduced the off-cycle emissions substantially on most vehicles. To comply with the proposed off-cycle standards for California low-emission vehicles and ultra-low-emission vehicles, these techniques will be a cost-effective method to reduce off-cycle emissions.

This paper discusses “Technical Excellence,” a set of qualities required by a Gas Turbine Engineering organization to be “Best In Class,” the key to a very successful business. The Aerospace Industry environment (market needs, economic pressures, and mode of operation) has been subjected to quantum changes during the last decade. This paper discusses how these changes in our environment are affecting the qualities required to achieve “Technical Excellence.” The author shows that, in spite of the increased challenges, “Technical Excellence” can be met by taking advantage of the very tools and methods derived from our Industry internal upheavals, provided we aggressively address the pitfalls inherent in such revolutionary changes.

The environmental impact of automobiles and components is of growing importance both in the public discussion and in the complex decision finding process for future car concepts. Especially more and more conflicts of objectives occur between technical, economical, ecological and political requirements. For a lasting improvement of environmental compatibility and recyclability as an element of the so-called „sustainable development” of automobiles and components, BMW is the first carmaker which has developed quantitative management tools /1, 2/. These component related instruments enable designers in the product development phase to evaluate different component variations practice-oriented and with an ecological perspective in mind. In this endeavor, BMW is placing its bets on „intelligent lightweight construction”, i. e., the ecologically-economically best component solution.

Conventional engine coolant systems use primarily ethylene glycol with inorganic inhibitors. New systems based on organic acids are currently being introduced into the market. The primary advantage of these systems is non-depletion of the inhibitors, allowing extended service intervals, where the coolant is changed between 100,000 - 200,000 miles versus 30,000 - 50,000 miles with the current systems utilizing inorganic inhibitors. This benefits the consumer and the environment. Plastic components are widely used in coolant systems where radiator end tanks, water pump impellers, inlets, outlets, and thermostat housings can be polymeric. A study was conducted in which a number of engineering plastics were exposed to conventional and long life coolants at elevated temperatures and pressures to determine the effect of the coolant. The intent of the study was to provide insight into plastics which can withstand the hot acid environment of extended life coolants during usage.

Life Cycle Assessment (LCA) has emerged as an analytical tool to provide environmental information on a product or process through its life cycle. The cost of conducting a comprehensive LCA can be prohibitive and so “streamlining” approaches have been tested by practitioners. However, the more simple the model, the less detail and resolution it has, and this may undermine the reasons for undertaking the study. LCA complexity should be matched to the need to address environmental concerns. Certain stages of the LCA methodology are not well developed, (eg impact and improvement assessments). To overcome these difficulties, a Design for Environment (DFE) method has been used alongside LCA to provide a process by which real improvements can be initiated.

LucasVarity, a major supplier to the automotive and aerospace industries, is in the process of developing an environmental design methodology (Design for Environment) to support its product introduction process. In this paper, a case study is used to examine the existing design process within one part of the company. Four design functions are identified, characterised and compared with the structures, methods and working practices of a company-specified product introduction process.

Fabric cleaning, like other human activities, results in impacts to the environment and poses other external costs to society. Cleaning and reuse of garments seems intuitively more environmentally sound than acquiring clothes for single wear and disposal provided that the costs of cleaning are less than purchasing new clothing. However, a more complex issue concerns the choice of cleaning method that would impose the lowest long term costs on society and is, thus, more sustainable. The textile cleaning industry in Canada and the USA has recently shown an interest in the application of aqueous or water-based cleaning methods, as a complement and partial replacement for the more traditional chemical ‘dry’ cleaning. Perchloroethylene (perc) is by far the most common chemical cleaning solvent used by commercial dry cleaning establishments throughout North America.

MAIN CONCLUSION - Banning the use of chlorine chemistry in the manufacture of only three of the major uses of chlorine (steel, Polyvinyl Chloride (PVC) and Titanium Dioxide) would result in a requirement to landfill an additional 24.6 billion pounds of waste each year (4.2 billion pounds auto related), raise serious issues regarding recycling with regard to PVC substitutes and raise the cost of related parts by some $2.0 billion a year. In addition, the use of available substitutes for chlorine-based compounds would result in a serious degradation in the quality and performance of automobiles manufactured in North America. PROCESS - Essentially, the process consisted of a micro economic analysis of the impact on the cost and performance of a “representative” automobile manufactured in North America and the differential environmental impact arising from the use of “available” substitutes.

The automobile painting is a very energy and emission (solvents) intensive process step in the production of automobiles with regard to the small amount of paint applied to the car body. The awareness has risen that cleaner production technologies must substitute end-of-pipe control technologies. If these technologies strive for being a competitive option in corporate decision-making process, not only their environmental but also their technical and economical performance has to be on the same or better level compared to conventional technologies. The approach of Life-Cycle Engineering (LCE) by IKP and PE investigates technical, environmental and economical aspects of products and technologies to analyze weak points and optimization potentials as well as to support product and technology development. LCE methodology was applied to the comparison of 1K, 2K, waterborne and powder clear coat systems for automobile painting in a multi-client project.

Products and services cause different environmental problems during the different stages of their life cycle. The Life Cycle Assessment tool aims to identify possibilities to improve the environmental behavior of the systems under consideration. Herefor it is necessary to systematically collect and interpret material and energy flows for all relevant processes. The whole life cycle of a system has to be considered to prevent the neglecting or shift of possible important environmental aspects. These results have to be included in the overall decision making process. In the last years PE developed the Life Cycle Engineering approach, which consist of the dimensions LCA, Life Cycle Cost and TQM. In order to support designers, engineers and decision makers to make better informed decisions, it is necessary to perform LCA studies and economical assessments at a very early stage in product design.