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Six laboratories capable of chassis-testing heavy-duty vehicles participated in a crosscheck program designed to compare emissions results from a Ford L-9000. The single-axle vehicle was shipped to each laboratory and tested through a series of UDDS and steady-state cycles. The resulting data were compared statistically using reproducibility and repeatability analyses. Although one lab produced some results that significantly differed from the other five, the remaining labs produced comparable results. TPM, CO and THC were the most variable while NOX and CO2 were most stable. Lab differences included atmospheric and environmental conditions, road-load curve application and drivers. Comparison of steady state and transient tests suggest that driver variability is not a major factor.

In the United States, the Coordinating Research Council (CRC) is the organization that for 58 years has been the mechanism through which the automotive and petroleum industries have undertaken to solve technical questions of mutual interest to the two industries. This paper presents a brief overview of the CRC, its relationship to SAE, its role in automotive research, current and future studies, and the need for worldwide cooperative research efforts. Discussion of current studies includes a CRC program to examine how to measure diesel particulate in the laboratory to accurately reflect on-road conditions and a study to develop a combustion chamber deposit (CCD) test for use as a research tool. Cooperative research is an important mechanism for generating the data necessary for solving well-defined technical issues of importance to both the automotive and petroleum industries and the public.

The first round of Federal Test Procedure (FTP) emissions testing of variable-fuel ethanol vehicles from the U.S. Federal fleet was recently completed. The vehicles tested include 21 variable-fuel E85 1992 and 1993 Chevrolet Lumina sedans and an equal number of standard gasoline Luminas. Results presented include a comparison of regulated exhaust and evaporative emissions and a discussion of the levels of air toxics, as well as the calculated ozone-forming potential of the measured emissions. Two private emissions laboratories tested vehicles taken from the general population of Federal fleet vehicles in the Washington, D.C., and Chicago metropolitan regions. Testing followed the standard U.S. Environmental Protection Agency's FTP and detailed fuel changeover procedures as developed in the Auto/Oil Air Quality Improvement Research Program.

The first round of emissions testing of flexible fuel methanol vehicles from the U.S. federal fleet was completed in 1995. The vehicles tested include 71 flexible fuel M85 1993 Dodge Spirits, 16 flexible fuel 1994 M85 Ford Econoline Vans, and a similar number of standard gasoline Dodge Spirits and E150 Ford Econoline Vans. Results presented include a comparison of regulated exhaust and evaporative emissions and a discussion of the levels of air toxins, and the ozone-forming potential (OFP) of the measured emissions. Three private emissions laboratories tested vehicles taken from the general population of federal fleet vehicles in the Washington D.C., New York City, Detroit, Chicago, and Denver metropolitan regions. Testing followed the standard U.S. Environmental Protection Agency's Federal Test Procedures (FTPs) and detailed fuel changeover procedures as developed in the Auto/Oil Air Quality Improvement Research Program.

The first round of emissions testing of light-duty alternative fuel vehicles placed in the U. S. federal fleet under the provisions of the Alternative Motor Fuels Act was recently completed. This undertaking included 75 Dodge B250 vans, of which 37 were dedicated compressed natural gas models, and 38 were standard gasoline controls. Data were collected on regulated exhaust emissions using the federal test procedures, and on a number of other quantities, through a statistically controlled program of investigation. Fuel economy results were also recorded. All test vehicles were operated in routine federal service activities under normal working conditions, adhering as closely as possible to Chrysler's prescribed maintenance schedules. The data analysis conducted thus far indicates that the compressed natural gas vehicles exhibit notably lower regulated exhaust emissions, on average, than their gasoline counterparts, and that these values are well within U.S.

Particulate and regulated gaseous emissions were characterized in a feasibility study for a 1994 Ford Taurus Flexible Fuel Vehicle (FFV) operating on five fuels. The five fuels included Federal Reformulated Gasoline (RFG); 85% fuel grade methanol and 15% gasoline (M85); 85% denatured ethanol and 15% gasoline (E85d); liquefied petroleum gas (LPG) meeting HD-5 specifications; and industry average compressed natural gas (CNG). The vehicle was operated fuel-rich to simulate a vehicle operating condition leading to increased production of particulate matter. This simulation was accomplished by using a universal exhaust gas oxygen sensor (UEGO) in connection with an external controller. Appropriate aftermarket conversion kits involving closed-loop control and adaptive learning capabilities allowed operation on the gaseous fuels. Particulate emissions were characterized by total mass and particle size.

Regulated and volatile organic exhaust species were characterized from a 1993 Chevrolet Lumina operating on CNG, LPG, and reformulated gasoline. For the gaseous fuels, aftermarket conversion kits were installed on the vehicle, and the resulting exhaust emissions were compared to the gasoline baseline results. For all of the fuels, the vehicle was operated over the chassis dynamometer portion of the Federal Test Procedure for light-duty vehicles at fuel/air equivalence ratios of 0.8, 1.0, and 1.2; and exhaust emissions were sampled both with and without the catalytic converter in place. Analyses of exhaust samples included determination of regulated exhaust emissions by CFR methods, hydrocarbon speciation and aldehyde and ketone analyses according to Auto/Oil Phase II methods, and the determination of trace exhaust species by mass spectral analysis methods.

Ethanol is one of several alternative transportation fuels considered for replacement of conventional gasoline and diesel fuel. In the past, the net energy yield for ethanol production from corn or sugar crops has been less than favorable. Recent research on ethanol production from energy crops such as grasses and trees (biomass) has indicated a potential for very favorable net energy yields. Use of renewable biomass or lignocellulosic materials as feedstocks for ethanol production can decrease carbon dioxide emissions and significantly increase total production capacity potential by broadening the feedstock resource. New biomass processing technology for ethanol production has generated increased interest in ethanol as an alternative transportation fuel.

Oil consumption has been identified as a contributor to diesel particulate exhaust emissions. The strict requirements for reduced diesel exhaust particulates in 1991 and in 1994 call for a much greater understanding of the level of oil consumption during transient as well as steady-state operations. A system has been assembled to continuously measure diesel engine oil consumption through on-line detection using sulfur as a tracer. The system requires a sulfur-free fuel, a high-sulfur diesel engine oil, an exhaust sampling system, and a sensitive detector. A series of engine tests were conducted using the sulfur-trace oil consumption measurement system. Variations in oil consumption at steady state and during transient operations have been measured. Quantitative measurement of oil consumption rates were confirmed by two separate calibration checks.

A theoretical model for predicting cetane number of primary reference fuels from parameters measurable by proton nuclear magnetic resonance is presented. This modeling technique is expanded to include secondary reference fuels, pure hydrocarbons, and commercial-type fuels. An evaluation of the ignition process indicated that not only hydrogen type distribution measurable by proton NMR, but also relative hydrogen population is important in predicting cetane number. Two mathematical models are developed. One predicts cetane number of saturate fuels and the second predicts cetane number of fuels containing aromatic components. The aromatic fuel model is tested using the ASTM Diesel Check Fuels and shown to predict within the standard error of the model.

A variety of multicomponent emergency transportation fuel formulations (diesel and spark) are evaluated by means of bench tests, single and multicylinder engine dynamometer tests, and chassis dynamometer tests. A wide range of alcohol and liquid hydrocarbon extenders are evaluated according to the tradeoff between performance loss and base fuel stretch-out with increasing extender concentration. Changes in gaseous exhaust emissions are also given in relative terms as a function of extender concentration. Detailed chemical composition and physical properties of blend combinations and individual blend constituents are also included. Collectively, these data form the basis for the DOE Emergency Fuel Utilization Guidebook.