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The 1977 Clean Air Act Amendments allow the U.S. Environmental Protection Agency to set high altitude emission standards for 1981-83, but specify that any such standards may not be more stringent than comparable sea level standards -- relative to 1970 emission levels. Since available high altitude emission data from 1970 models were incomplete and controversial, the Motor Vehicle Manufacturers Association contracted with Automotive Testing Laboratories, Inc. to test a fleet of 25 1970 cars. Results of the test program showed average increases in emissions at Denver's altitude, compared to sea level, to be about 30% for evaporative HC, 57 to 60% for exhaust HC, 215 to 247% for CO and -46 to -47% for NOx. Corresponding HC and CO exhaust emission baselines would be 6.4 to 6.6 and 108 to 118 g/mi respectively.

Since 1978 Ford Motor Company has been surveying the fuel economy of employes who lease new light duty vehicles from the Company. Winter and summer survey data for the three years are analyzed and compared. Car results show a significant and steady increase in average on-road fuel economy over the three year period. The percent differential between EPA measured and actual on-road fuel economy has lessened substantially since 1978. Furthermore, the percent difference between EPA and on-road is essentially constant over the range of EPA values for each of the three years. Limited fuel economy results for 1980 trucks are also discussed.

Diesel Particulate Filters (DPF) are widely used to meet 2007 and beyond EPA Particulate Matter (PM) emissions requirements. During the soot loading process, soot is collected inside a porous wall and eventually forms a soot cake layer on the surface of the DPF inlet channel walls. A densely packaged soot layer and reduced pore size due to Particulate Matter (PM) deposition will reduce overall DPF wall permeability which results in increasing pressure drop across the DPF substrate. A regeneration process needs to be enacted to burn out all the soot collected inside the DPF. Soot mass is not always evenly distributed as the distribution is affected by the flow and temperature distribution at the DPF inlet. As a result, the heat release which is determined by the burn rate is locally dependent. High temperature gradients are often found inside DPF substrate as a result of these locally dependent burn rates.

Engines are assigned big subjects such as low emission and low fuel consumption as well as higher output (higher efficiency) in the latest trend of environmental protection. In order to meet these requirements, Air/Fuel ratio of recent high performance engines is being arranged leaner than that of conventional engines. As a result exhaust valve seat inserts used in these engines have problems of their wear resistance because of high exhaust gas temperature. By analyzing wear mechanism under the lean burn conditions, authors developed material for exhaust valve seat inserts which show superior wear resistance under high operating temperature. For the purpose to enhance heat resistance, authors added alloy steel powder for matrix powder and used hard particles which have good diffusion with matrix. The developed material does not include Ni and Co powders for cost saving and has superior machinability.

There is a movement to apply emission control in a marine engine as well due to high public awareness of environmental concern in the United States. We started at the development of 3-seater Personal Watercraft (PWC) equipped with 4-stroke engines in taking environment conformity and potential into account. The PWC employed series 4-cylinder 1100cc displacement engine that has been used for mass production motorcycles. The engine was modified to satisfy requirements for PWC, as a marine engine, such as performance function and corrosion. In order to achieve greater or equal power/weight ratio as against two-stroke PWCs, a four-stroke engine for PWC with an exhaust turbo charger was developed. As a result, we succeeded in developing an engine that attained top-level running performance and durability superior to competitors' 2-stroke engines.

A fleet of 50, 1986-1987 model year cars designed for unleaded gasoline has been tested on the road and on a chassis dynamometer over 5 driving cycles and a wide range of other manoeuvres including steady speeds. It was found that the fuel consumption of this fleet was 17 to 23% (depending on test cycle) less than that of a corresponding fleet to leaded fuelled cars of 1980 model year average. Exhaust emissions were significantly lowered in the range of 45 to 93%. However trend line analysis of the several data sets indicates that the ULG fleet has about 6% higher fuel consumption than would have been expected if there had been a continuing evolution of leaded vehicle technology. The data base produced has applicability to a wide range of planning and design tasks, and those illustrated indicate the effects of speed limit changes and advisory speed signs on fuel consumption and emissions.

Over the past few decades, Homogeneous Charge Compression Ignition (HCCI) or Controlled Auto-Ignition (CAI) if it is fuelled with gasoline type of fuels has shown its potential to overcome the limitations and environmental issue concerns of the Spark Ignition (SI) and Compression Ignition (CI) engines. However, controlling the ignition timing of a CAI engine over a wide range of speeds and loads is challenging. Combustion in CAI is affected by a number of factors; the local temperature, the local composition of the air/fuel mixture, time and to a lesser degree the pressure. The in-cylinder engine charge flow fields have significant influences on these factors, especially the local gas properties, which leads to the influences towards the CAI combustion. In this study, such influences were investigated using a Computational Fluid Dynamics (CFD) engine simulation package fitted with a real optical research engine geometry.

This paper provides a long-term view of the deployment of environmental technologies for light-duty vehicles in the United States and their implications for other vehicle attributes. It considers technologies for controlling tropospheric air pollutants, improving fuel economy, and reducing corollary greenhouse gas emissions. Since the introduction of the first controls to improve ambient air quality in the early 1960s, these technologies have gone from simple crankcase vapor recirculation and positive control valve systems and adjustments in carburetor air/fuel ratio and spark timing to systems that continuously control and monitor vehicle operations to optimize emissions reductions and fuel economy. Not only have these technologies produced major benefits for public health, the environment, and energy conservation, but they have also fundamentally altered the characteristics of the vehicles we drive today. And future regulations will reform the vehicle fleet even further.

Abstract In the United States (USA), transportation is the largest single source of greenhouse gas (GHG) emissions, representing 27% of total GHGs emitted in 2020. Eighty-three percent of these came from road transport, and 57% from light-duty vehicles (LDVs). Internal combustion engine (ICE) vehicles, which still form the bulk of the United States (US) fleet, struggle to meet climate change targets. Despite increasingly stringent regulatory mechanisms and technology improvements, only three US states have been able to reduce their transport emissions to the target of below 1990 levels. Fifteen states have made some headway to within 10% of their 1990 baseline. Largely, however, it appears that current strategies are not generating effective results. Current climate-change mitigation measures in road transport tend to be predominantly technological.

Although concerns have been raised that the performance of activated carbon canisters will decrease when exposed to air at higher humidities, results of a recently conducted test program do not substantiate these concerns. The results show that the purge efficiency and the working capacity of canisters that are purged with air at 75 grains per pound of dry air (GPPDA) humidity are equal or greater than those obtained with 50 GPPDA humidity purging. The results have been submitted to the California Air Resources Board (ARB) for use in aligning their evaporative emission testing regulations with the regulations promulgated by the U. S. Environmental Protection Agency (EPA).

Soot particles emitted from modern diesel engines, despite significantly lower total mass, show higher reactivity and toxicity than black-smoking old engines, which cause serious health and environmental issues. Soot nanostructure, i.e. the internal structure of soot particles composed of nanoscale carbon fringes, can provide useful information to the investigation of the particle reactivity and its oxidation status. This study presents the nanostructure details of soot particles sampled directly from diesel flames in a working diesel engine as well as from exhaust gases to compare the internal structure of soot particles in the high formation stage and after in-cylinder oxidation. Thermophoretic soot sampling was conducted using an in-house-designed probe with a lacy transmission electron microscope (TEM) grid stored at the tip.

In response to growing concern over the validity of the EPA fuel economy numbers, the Department of Energy undertook a study of actual on-road fuel economy as it compares to the EPA numbers. This report covers the development of the data base for that study, the analysis techniques used for the initial phases of the work, and the preliminary results of that analysis. Data on over 5000 in-use vehicles were collected for model years 1974-1977. Data were obtained from a number of private and government groups for vehicles in fleet and typical consumer use, from on-road tests, and from in-use dynamometer tests. Comparisons using linear regressions were made between these mpg values and the EPA certification results for the same models. The results describe these differences as a function of vehicle mpg and model year. Other more specific comparisons are also made. An analysis of in-use fuel economy ranking, compared to the ranking by the EPA mpg numbers, is presented.

The U. S. Environmental Protection Agency is studying the merits of four strategies to reduce hydrocarbon emissions from motor vehicles. The four strategies include onboard control of vehicle refueling emissions. Stage II controls on service stations, tightening of existing vehicle evaporative control regulations, and restrictions on gasoline volatility. In this paper, emissions reductions and costs projected for each strategy will be compared. Of the four strategies, onboard refueling controls on new cars would be the most effective in reducing nationwide hydrocarbon emissions; however, the incremental emission reduction would be relatively small compared with future reductions from controls already in place.

Used ATs (automatic transmissions) in the market were analyzed using a remanufacturing process, and causes of troubles/defects were investigated. By providing specific parts of an AT with sufficiently ample working-stress levels at the design stage, the remanufacturing cycle can be better controlled and managed, while still maintaining the quality of ATs at the highest levels. Scheduled part changes performed as part of this process successfully make an AT returnable to new-car assembly lines for reinstallation. This fully recycled AT enables reductions in steel and aluminum consumption, and thus contributes substantially to environmental protection efforts.

This paper describes a method of using the total emission concept for conveniently assessing the accuracy of emission measurements. The measured total HC emissions are treated as unburned fuel (C8 basis) plus burning zone HC (C1 basis). Statistical analysis shows that the emission test data may be questionable if the total emission calculation exceeds the range of 100 +/- 2σ*. This paper also describes a technique to determine the Air to Fuel (A/F) ratio for two-stoke engines. This method may be used to calculate the overall A/F and burning zone A/F for DI two-stroke engines and for engines using oxygenated fuel. Twenty-five OMC engines have been tested by following EPA emission test procedure. The total emission and A/F analysis for these tests indicate that the new method is a very useful tool for assessing A/F and the accuracy of emission measurements. This technique reduces the emission test errors and shortens engine calibration and development time.

Vehicle weight reduction has become one of the most crucial problems in the automotive industry because that increasingly stringent regulatory requirements, such as fuel economy and environmental protection, must be met. The lightweight design needs to consider various vehicle attributes, including crashworthiness and stiffness. Therefore, in essence, the vehicle weight reduction is a typical Multidisciplinary Design Optimization problem. To improve the computational efficiency, meta-models have been widely used as the surrogate of FE model in the multidisciplinary optimization of large structures. However, these surrogate models introduce additional sources of uncertainties, such as model uncertainty, which may lead to the poor accuracy in prediction. In this paper, a method of corrected surrogate model based multidisciplinary design optimization under uncertainty is proposed to incorporate the uncertainties introduced by both meta-models and design variables.

CO2 emission is more serious in recent years and automobile manufacturers are interested in developing technologies to reduce CO2 emissions. Among various environmental-technologies, the use of solar roof as an electric energy source has been studied extensively. For example, in order to reduce the cabin ambient temperature, automotive manufacturers offer the option of mounting a solar cell on the roof of the vehicle [1]. In this paper, we introduce the semi-transparent solar cell mounted on a curved roof glass and we propose a solar energy management system to efficiently integrate the electricity generated from the solar roof into internal combustion engine (ICE) vehicles. In order to achieve a high efficiency solar system in different driving, we improve the usable power other than peak power of solar roof. Peak power or rated power is measured power (W) in standard test condition (@ 25°C, light intensity of 1000W/m2(=1Sun)).

The drag coefficient at zero yaw angle is the single parameter usually used to define the aerodynamic drag characteristics of a passenger car. However, this is usually the minimum drag condition and will, for example, lead to an underestimate of the effect of aerodynamic drag on fuel consumption because the important influence of the natural wind has been excluded. An alternative measure of aerodynamic drag should take into account the effect of nonzero yaw angles and a variant of wind-averaged drag is suggested as the best option. A wind-averaged drag coefficient (CDW) is usually derived for a particular vehicle speed using a representative wind speed distribution. In the particular case where the road speed distribution is specified, as for a drive cycle to determine fuel economy, a relevant drag coefficient can be derived by using a weighted road speed.

Many factors can be cited which produce differences between the fuel economy values obtained during the exhaust emission certification process and the economy experienced by car owners. Admittedly, all laboratory tests are compromised by many assumptions, approximations, and practical test limitations. The main value of the EPA test procedure is that it has provided a uniform test method for all manufacturers which produces vast amounts of comparative fuel economy information. Changes to the procedure to make it more “representative” have reduced its usefulness for comparisons to previous years. The concept of labeling cars with a “representative” fuel economy value is certain to result in some customer misinformation and dissatisfaction. At best, current labeling methods can be expected to indicate real vehicle differences only when label values differ by more than 2 mi/gal (0.85 km/l).