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This paper reports the results of an exhaust emissions characterization from the non-catalyst control systems employed on the Mazda RX-4 rotary, the Honda CVCC, and the Chrysler electronic lean burn. Throughout the paper, exhaust emissions from these vehicles are compared to those from a Chrysler equipped with an oxidation catalyst and an air pump. The emissions characterized are carbon monoxide, hydrocarbons, nitrogen oxides, sulfur dioxide, sulfates, hydrogen sulfide, carbonyl sulfide, hydrogen cyanide, aldehydes, particulate matter, and detailed hydrocarbons. A brief description of the sampling and analysis procedures used is included within the discussion.

This work presents a method for simultaneously capturing visible and infrared images along with pressure data in an optical Diesel engine based on the International 4.5L VT275 engine. This paper seeks to illustrate the merits of each imaging technique for visualizing both in-cylinder fuel spray and combustion. The engine was operated under a part load, high simulated exhaust gas recirculation operating condition. Experiments examining fuel spray were conducted in nitrogen. Overlays of simultaneously acquired infrared and visible images are presented to illustrate the differences in imaging between the two techniques. It is seen that the infrared images spatially describe the fuel spray, especially fuel vapors, and the fuel mixing process better than the high-speed visible images.

A mathematical model of an automobile's emission rate is described. This model can be used to calculate the amounts of hydrocarbons, carbon monoxide, and oxides of nitrogen emitted by individual or groups of automobiles being driven over any known driving sequence. The development of the model requires the amounts of three pollutants given off by individual automobiles over short duration driving sequences (modes). The validity of the model is investigated by using it to calculate the amounts of each pollutant given off by individual automobiles over the hot transient portion (first 505 s) of the Federal Test Procedure driving sequence. These predicted emissions are then compared with observed amounts emitted from each automobile. Further, the ability of the model to predict emissions is investigated in light of the reproducibility of actual automobile emissions measured in replicated tests. These analyses indicate that the model performs extremely well.

A baseline testing program was designed and implemented by EPA wherein 78 vehicles were tested in 5 laboratories. The objectives of this study were to 1) obtain sulfate emission factors on a wide variety of different in-use vehicles using current and advanced emission control methods, and 2) determine the effect on sulfate emissions of vehicles meeting increasingly stringent gaseous emissions standards. The program was designed such that the vehicles were divided into the following classes: 1) production non-catalyst vehicles, 2) production catalyst vehicles - grouped according to emissions standards, 3) advanced non-catalyst vehicles, 4) advanced catalyst vehicles, and 5) fleet vehicles.

A stratified charge research engine and test stand were designed and built for this work. The engine was designed to exhibit some of the desirable traits of both the premixed charge gasoline engine and modern diesel engine. This spark ignition engine is fueled by M100 (99.99% pure methanol), operates under high compression (19.3:1) and uses direct fuel injection to form a stratification of the fuel-air mixture in the cylinder. The beginning of the combustion event of the stratified mixture is triggered by spark plug discharge. The primary goal of this project was to evaluate the feasibility of using a removable integral injector ignition source insert, which allows a convenient method of changing the relative location of the fuel injector to the ignition source, as well as the compression ratio, squish height, and bowl volumes. This paper provides an explanation of the hardware included in the experimental setup of the engine and selection of the direct injector configuration.

Of all existing modes of transportation, onroad motor vehicles are the largest contributor to greenhouse gas emissions and fuel usage. The Environmental Protection Agency and the National Highway Traffic Safety Administration finalized regulations in April 2010 to reduce greenhouse gas emissions and improve fuel economy for 2012-2016 model year light-duty vehicles. In November 2010, both agencies jointly proposed the first ever greenhouse gas standards for medium- and heavy-duty trucks which are expected to take effect for model years starting in 2014. Vehicles of light-duty families are subject to mandatory testing for certification and compliance. Unlike the light-duty sector where a vast majority of vehicles are mass produced for generally similar purposes, medium- and heavy-duty vehicles are commonly custom-made.

This paper reviews the development of the LA 4 road route, and discusses efforts directed toward development of a short repetitive dynamometer cycle based upon the road route Also described are the instrumentation, methods, and selection process used to obtain a speed profile of a typical drive over the 12 mile long route The methods used to shorten the speed profile to 7.5 miles, and to shorten the average trip length, while preserving trip description such as average speed, idle time, number of stops, etc., are explained. A measure of the correlation of emissions from vehicles driven over the EPA Urban Dynamometer Driving Schedule (UDDS) and over the full LA 4 driving schedule is provided. The UDDS is a speed-trace consisting of 18 profiles. separated by idle periods of 0-39 s duration The schedule covers 7.46 miles in 1372 s for an average speed of 19.6 mph.

A program was conducted to determine the effect of temperature and humidity on exhaust emissions from automotive engines. The objective was to determine if the effects were of sufficient magnitude to require the application of correction factors to measured exhaust emissions to standard humidity and temperature values. Both American and foreign-made vehicles were tested at 20 combinations of ambient temperature and humidity. The effect of temperature and humidity was found to be both unpredictable and of little significance for hydrocarbon and carbon monoxide emissions. No correction factors were developed for these exhaust gas constituents. The effect of temperature was found to be of little significance for oxides of nitrogen. However, humidity effects were found to be significant and predictable for oxides of nitrogen.

A detailed study is undertaken to examine how 2010+ diesel engine exhaust emissions change when a soybean-derived B20 biodiesel fuel is used instead of a conventional ultra-low sulfur diesel fuel and to investigate how these changes impact the aftertreatment system. Particulate matter (PM) emissions for each fuel are characterized in terms of mass emissions, size distributions, organic versus soot fraction, metals content, and particle morphology. PM mass recorded by Dekati Mass Monitor, thermal analysis of quartz filters, and calculated from particle size distributions consistently shows a 2 - 3 fold decrease in engine-out soot emissions over a wide mid-load range when changing from ULSD to B20 fuel. This is partly due to a decrease in particle number and partly to a decrease in average size. HC and NO emissions, in contrast, exhibit little change with fuel type.

Evaporative emission tests were performed on forty in-use late model passenger cars using different volatility fuels and varying temperatures. Results show that diurnal and hot soak emissions are quite sensitive to temperature, and also that the temperature sensitivity increases with the use of higher volatility fuels. Empirical models were developed to express diurnal and hot soak emissions as a function of fuel volatility and temperature.

The Environmental Protection Agency (EPA) recently tested a clean diesel fuel developed by Dion & Sons for use in stationary sources. This fuel is known as Amber 363 in Southern California and its technology is licensed outside of the Southern California area to Shell Oil Products Company for use as a stationary source fuel. The fuel, hereafter referred to as “Shell LOW NOX Fuel,” was tested in a 1990 model year heavy heavy-duty diesel engine using both the transient Federal Test Procedure (FTP) for on-highway heavy-duty engines, the steady-state FTP for nonroad heavy-duty engines, and the steady-state generator set test cycle. For each test, EPA measured hydrocarbon (HC), carbon monoxide (CO), nitrogen oxides (NOx) and particulate matter (PM) emissions. Transient testing showed that the Shell LOW NOX Fuel lowers NOx, HC and PM emissions with no statistically significant change in CO emissions for both cold-starts and hot-starts when compared to diesel certification test fuel.

This paper summarizes an investigation of reductions in exhaust emission levels attainable using various techniques appropriate to gasoline engines used in vehicles over 14,000 lbs GVW. Of the eight gasoline engines investigated, two were evaluated parametrically resulting in an oxidation and reduction catalyst “best combination” configuration. Four of the engines were evaluated in an EGR plus oxidation catalyst configuration, and two involved only baseline tests. Test procedures used in evaluating the six “best combination” configurations include: three engine emission test procedures using an engine dynamometer, a determination of vehicle driveability, and two vehicle emission test procedures using a chassis dynamometer. Dramatic reductions in emissions were attained with the catalyst “best combination” configurations. Engine durability, however, was not investigated.

A fleet of 64 heavy-duty 1970-71 model trucks and buses powered by a variety of diesel engines were tested periodically to determine exhaust smoke behavior. Smoke tests were made when the vehicle was new or nearly new and at four month intervals thereafter, or until 160,934 km (100,000 miles) odometer reading was reached. Gaseous emissions of hydrocarbon (HC), carbon monoxide (CO), and nitric oxide (NO) were measured at one point early in the project. Both smoke and gaseous emission tests were performed with chassis versions of the engine dynamometer Federal Test Procedures (FTP). Results in terms of “a” (acceleration), “b” (lugging), and “c” (peak) smoke factors versus mileage are reported for the 13 engine-vehicle-application groupings.

The Environmental Protection Agency (EPA) is developing emission standards for nonroad spark-ignition engines rated over 19 kW. Existing emission standards adopted by the California Air Resources Board for these engines were derived from emission testing with new engines, with an approximate adjustment applied to take deterioration into account. This paper describes subsequent testing with two LPG-fueled engines that had accumulated several thousand hours of operation with closed-loop control and three-way catalysts. These engines were removed from forklift trucks for characterization and optimization of emission levels. Emissions were measured over a wide range of steady-state points and several transient duty cycles. Optimized emission levels from the aged systems were generally below 1.5 g/hp-hr THC+NOx and 10 g/hp-hr CO.

This report describes the results of a surveillance study initiated by the U.S. Environmental Protection Agency to measure gaseous exhaust emissions from 1020 light-duty motor vehicles. This project was the second effort in a continuing program using the CVS Federal Test Procedure. Selected privately-owned vehicles, drawn randomly from six metropolitan areas, were tested in as-received condition. The emissions data obtained from these 1966-1972 model-year vehicles are reported in grams per mile of unburned hydrocarbons, carbon monoxide, carbon dioxide and oxides of nitrogen while fuel economy is reported in mpg as determined over the Federal Driving Schedule.

Motor vehicles are seldom used in ambient conditions like those defined in current emission regulations. For example, most of the year average temperatures across Europe fall much below the range of legislative testing. Furthermore, it has been widely demonstrated that cold-starts at low ambient temperature increase the emissions. Therefore, there is a growing need to broaden the range of legislative emissions tests and set a separate low-ambient test with respective emission standards. This paper gives emissions test results form a joint research programme between Sweden and Finland. Altogether 11 late model gasoline-fueled TWC vehicles were tested at ambient temperatures of +22 and -7 °C using a variety of different driving cycles. Apart from the driving schedule, other test parameters like vehicle preconditioning, manual vs. automatic transmission and the effect of external cooling were studied and discussed.

The fuel economy data obtained from the emission tests run by the U.S. Environmental Protection Agency (EPA) have been used to show passenger car fuel economy trends from model year 1957 to present. This paper adds the 1975 model year to the historical trend and concentrates on comparisons between the 1975 and 1974 models. Methodologies which allow different 1975 vs 1974 comparisons to be made have been developed. These calculation procedures allow the changes in fuel economy to be determined separately for emission control systems, new engine-vehicle combinations and model mix shifts. Comparisons have been calculated not only for the fleet as a whole but for each of the 13 manufacturers who were certified as of the time this paper was prepared. The net change in fuel economy for the fleet has been estimated at +13.8% comparing the 1975 models to the 1974 models assuming no model mix change occurs.

Seven motorcycles, ranging in size from 100 to 1200 cm3, were tested for emissions characterization purposes. They were operated on the federal seven-mode test procedure (for 1971 and older light-duty vehicles), the federal LA-4 test procedure (for 1972 and later LDVs), and under a variety of steady-state conditions. Four of the machines tested had 4-stroke engines, and the other three had 2-stroke engines. Emissions which were measured included hydrocarbons, CO, CO2, NO, NOx, O2, aldehydes, light hydrocarbons, particulates, and smoke. Emissions of SOx were estimated on the basis of fuel consumed, and evaporative hydrocarbon losses were also estimated. Crankcase “blowby” emissions from one 4-stroke machine were measured. The impact of motorcycles on national pollutant totals was estimated, based on the test results and information from a variety of sources on national population and usage of motorcycles.

This paper discusses some trends and influencing factors in passenger car fuel economy. Fuel economy and fuel consumption were calculated by a carbon balance method from HC, CO, and CO2 emissions measured by the 1972 Federal Test Procedure. The information presented was derived from nearly 4000 tests of passenger cars ranging from 1957 production models to 1975 prototypes. Data are presented for various model year and vehicle weight categories. Trends in fuel economy are discussed on an overall sales-weighted basis and for each individual weight class. Some of the factors that influence fuel economy are quantified through the use of a regression analysis. Particular emphasis is placed on the differences in fuel economy between those vehicles that were subject to federal emission regulations and those vehicles that were not. Three ways to characterize vehicle specific fuel consumption are presented and discussed.

The use of fuel economy data from the Federal Test Procedure (FTP) has provided a substantial amount of data on the fuel economy of passenger cars in urban driving conditions. Since the FTP does not represent the type of driving done in rural areas, especially on highways, a driving cycle to assess highway fuel economy was a desirable supplement to the FTP. The new Environmental Protection Agency (EPA) “highway” cycle was constructed from actual speed-versus-time traces generated by an instrumented test car driven over a variety of nonurban roads and highways. This cycle reflects the correct proportion of operation on each of the four major types of nonurban roads and preserves the non-steady-state characteristics of real-world driving. The average speed of the cycle is 48.2 mph and the cycle length is 10.2 miles, close to the average nonurban trip length.