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Comparing with the previous Auto/Oil programs, the total plan and current status of the air quality modeling study in JCAP are presented. The total plan of air quality modeling study has the following characteristics: 1) Vehicle emission inventory program is developed by considering the original features of Japan. 2) Not only the urban air quality but also the road sides pollutants dispersion is evaluated. 3) The chemical reaction model for the secondary particulate formations is developed on the basis of the smog chamber experiments. 4) For the cost-effectiveness analysis of vehicle/fuel technologies, the output of the air quality modeling will be combined with the cost data of new vehicle emission reduction technologies As the first step, preliminary modeling studies are conducted to understand the overall tendency of the air quality change toward 2010 in Tokyo urban area.

Variations in air-fuel ratio within a 16-valve port-injection spark-ignition engine have been examined as a consequence of rapid transients in load at constant speed with fuel injection controlled by the production engine-management system and by a custom-built controller. The purpose was to minimize excursions from stoichiometry by the use of a controller to impose an injection strategy, guided by results obtained with the production management system. The strategy involves a model that takes account of manifold filling and the delays in transport of fuel from the injectors to the cylinder. The results show that the excursions in air-fuel ratio from stoichiometry were reduced from more than 25% to 6%.

Six commercial different additive packages to be used in the Venezuelan Internal Market Diesel formulations were evaluated in terms of their performance in corrosion inhibition, oxidation stability, injector cleanliness and emissions, as well as fuel economy improvement. Laboratory, field and bench tests were carried out. In laboratory tests, additives evaluated were added to four Venezuelan Diesel fuel formulations at the recommended supplier doses: corrosion (ASTM D665), oxidation stability (ASTM D2274), emulsification (ASTM D1094). Also, physicochemical properties required by Venezuelan Diesel fuel specifications were evaluated. Three different trucks (per additive) were run in fleet tests in order to determine injector cleanliness performance. Truck injector flow was measured in every injector, according to ISO 4010 procedure, before and after 5000-6000 km field accumulations. Two trucks were run without additive dosification, and were used for base line comparison.

In spite of the efforts of related industries, the air pollution situation particularly in urban areas of Japan is not satisfactory. It has been shown that air pollution is caused mainly by increased automotive traffic and increased penetration of diesel vehicles. Air-quality problems will become much more complicated and more severe in the future with increased emphasis on reducing air pollution and global warming. These situation will require continuous reduction of automobile emissions. In order to obtain cleaner exhaust emissions, cooperative studies between vehicle and fuel technologies are considered to be essential, and AQIRP in the United States and Auto/oil Program in Europe were already conducted to develop the best combination of measures for air pollution improvement. In 1996, Japan Clean Air Program (JCAP) was launched by Petroleum Energy Center (PEC) in cooperation with the Petroleum Association of Japan (PAJ) and the Japan Automobile Manufacturers Association (JAMA).

Emissions of six 32 passenger transit buses were characterized using one of the West Virginia University (WVU) Transportable Heavy Duty Emissions Testing Laboratories, and the fixed base chassis dynamometer at the Colorado Institute for Fuels and High Altitude Engine Research (CIFER). Three of the buses were powered with 1997 ISB 5.9 liter Cummins diesel engines, and three were powered with the 1997 5.9 liter Cummins natural gas (NG) counterpart. The NG engines were LEV certified. Objectives were to contrast the emissions performance of the diesel and NG units, and to compare results from the two laboratories. Both laboratories found that oxides of nitrogen and particulate matter (PM) emissions were substantially lower for the natural gas buses than for the diesel buses. It was observed that by varying the rapidity of pedal movement during accelerations in the Central Business District cycle (CBD), CO and PM emissions from the diesel buses could be varied by a factor of three or more.

Many efforts have been made to apply the diesel exhaust particulate after-treatment system in practical use during the past ten years. In this paper, a diesel exhaust particulate after-treatment system with microwave energy as its external regeneration energy source is described, and the microwave regeneration characteristics of the diesel exhaust particulate after-treatment system developed are studied. The experimental results show that the regeneration efficiency can reach up to 80% with a wide regeneration window and a suitable regeneration duration. The effect of air supply on filter regeneration is also observed. It is proven that the microwave regeneration technique employed in the system is simple, effective and reliable.

Speed-time and video data were logged for tractor-trailers performing local deliveries in Akron, OH. and Richmond, VA. in order to develop an emissions test schedule that represented real truck use. The data bank developed using these logging techniques was used to create a Yard cycle, a Freeway cycle and a City-Suburban cycle by the concatenation of microtrips. The City-Suburban driving cycle was converted to a driving route, in which the truck under test would perform at maximum acceleration during certain portions of the test schedule. This new route was used to characterize the emissions of a 1982 Ford tractor with a Cummins 14 liter, 350 hp engine and a 1998 International tractor with a Cummins 14 liter, 435 hp engine. Emissions levels were found to be repeatable with one driver and the driver-to-driver variation of NOx was under 4%, although the driver-to-driver variations of CO and PM were higher.

A methodology has been developed to enable a single, gaseous sample to be collected from the diluted exhaust stream of heavy duty diesel engines operating over the European 13 mode ECE R49 emission cycle. The sample consists of timed contributions of dilute exhaust gas from each mode (weighted appropriately) to provide a gas sample that is representative of the complete cycle. The sample is collected in a Tedlar bag prior to GC analysis for individual hydrocarbon speciation. This methodology has also been extended to allow for the collection of a representative carbonyl sample using 2,4-dinitrophenyl-hydrazine (2,4-DNPH) impregnated cartridges. Results obtained from these systems are reported and compared to results obtained from light duty (diesel and gasoline) investigations.

Several candidate oxygenates have been proposed for use with diesel fuel. This paper examines the safety and health issues associated with the use of these oxygenates. The primary fire safety hazard associated with the use of oxygenates is increased diesel fuel volatility and consequent low flash point. Peroxide formation may be a hazard for some oxygenates, but no quantitative information on the extent of the hazard was located for any of the candidate oxygenates. Little information is available on inhalation, ingestion, or skin exposure toxicity hazards. Of the candidate ethers, only pentyl ether, 2-ethoxyethyl ether (diethyl carbitol), and dibutoxymethane (butylal) do not have low flash points or significant known toxicity problems.

This work includes an assessment of the lubricity of Greek road diesel fuel of low sulfur content, and the effect of the addition of two different types of biodiesel which can be produced from raw materials abundant in the Mediterranean area. In this study, a series of representative fuels of the Greek fuel market were tested. In some of them, the lubricity was measured three times, during a period of three months from the day of each sample was produced. In all cases a decrease of the wear scar diameter (WSD) was measured; this behaviour could be attributed to the oxidation reactions that take place during the storage period. In order to monitor the effect of the addition of biodiesel on the lubricity of road diesel, biodiesels produced from sunflower oil and olive oil were used. The use of rape seed oil biodiesel as a diesel fuel substitute is a commercial event in Central Europe; in the United States the soybean oil biodiesel has been examined in detail.

The emissions reduction benefits of Fischer-Tropsch (FT) diesel fuel have been shown in several recent published studies in both engine testing and in-use vehicle testing. FT diesel fuel shows significant advantages in reducing regulated engine emissions over conventional diesel fuel primarily to: its zero sulfur specification, implying reduced particulate matter (PM) emissions, its relatively lower aromaticity, and its relatively high cetane rating. However, the actual effect of FT diesel formulation on the in-cylinder combustion characteristics of unmodified modern heavy-duty diesel engines is not well documented. As a result, a Navistar T444E (V8, 7.3 liter) engine, instrumented for in-cylinder pressure measurement, was installed on an engine dynamometer and subjected to steady-state emissions measurement using both conventional Federal low sulfur pump diesel and a natural gas-derived FT fuel.

Fischer-Tropsch (FT) conversion of gasification products to liquid hydrocarbon fuel commonly includes FT synthesis followed by mild refining of the FT synthetic oil into diesel, kerosene, and naphtha, each defined by a specific boiling range. These FT products are derived typically by mixing condensable gaseous reactor effluent (∼C5-C20) with hydrocracked liquid reactor effluent (∼C20+). This mixture of FT liquids (FTL), is then hydrotreated and distilled to yield the desired products. This paper evaluates compression-ignition engine performance during preliminary tests of the condensable gaseous reactor effluent (∼C5-C20) portion of the (FTL) from a Syntroleum Corporation plant. Engine operability, maximum torque, fuel economy and emissions were evaluated for both FTL and mixtures of FTL with gasoline, hexanes, diethyl ether, and ethanol. Emphasis was placed on particulate and NOx emissions. However, hydrocarbon, carbon dioxide, and oxygen concentrations were also followed.

A new proportional collection system for extremely low tailpipe emission measurement in transient conditions has been developed. The new system can continuously sample a minute flow of exhaust gas, at a rate that is proportional to the engine exhaust rate. A zero grade gas dilution technique is utilized to prevent the influence of pollutants in atmospheric air that are the same concentration level as those in the exhaust gas. The system has accuracy within ±5%. For the direct exhaust gas flow meter, a pitot tube type flow meter is utilized as it is simple, heat resistant, sufficiently accurate and has low flow-resistance characteristic. For the collection and dilution controllers, two mass flow controllers (MFC) were adopted. The MFCs' output can be adversely influenced by variation of the specific heat of the sample gas, resulting in flow reporting error.

Due to increasing interest in the emissions-producing characteristics of today's automobiles, emissions testing procedures have come under close scrutiny. In addition, development of procedures to measure emissions of vehicles operating in “on-road” conditions have been proposed to gain knowledge of the instantaneous mass flow rates of various legislated gaseous emissions. The problem with the measurement of these instantaneous flow rates is that the responses of modern emissions analyzers to transients are too slow for reliable results. Therefore, a method for improving the dynamic response of these instruments is needed. A method is described which utilizes generalized predictive control theory concepts in conjunction with system identification techniques to produce a software “filter” which reconstructs the distorted output of these analyzers.

This paper explores the extent to which standard dilution tunnel measurements of motor vehicle exhaust particulate matter modify particle number and size. Steady state size distributions made directly at the tailpipe, using an ejector pump, are compared to dilution tunnel measurements for three configurations of transfer hose used to transport exhaust from the vehicle tailpipe to the dilution tunnel. For gasoline vehicles run at a steady 50 - 70 mph, ejector pump and dilution tunnel measurements give consistent results of particle size and number when using an uninsulated stainless steel transfer hose. Both methods show particles in the 10 - 100 nm range at tailpipe concentrations of the order of 104 particles/cm3.

The E-35 “Running Loss” program was planned in the fall of 1996, and conducted in the summer of 1997, as the third part of a series of Coordinating Research Council (CRC) sponsored evaporative emission test programs. One hundred and fifty vehicles (half cars - half light duty trucks) were recruited at a local I/M lane, and tested for running loss emissions at the ATL Facility in Mesa, AZ. The previous CRC programs had studied hot soak, and then diurnal emissions. Running loss emissions were measured in a Running Loss SHED (RL-SHED) for a 25 minute, 7.5 mile trip on a hot summer day (95°F). Vehicles from model years 1971 through 1991 were tested. A wide range in emission levels was observed - from a low of 0.13 g/mile to 43 g/mile. The test results were not able to establish whether car emissions are different, or the same, as light duty trucks. The major causes of the high emissions were liquid leaks on carburetor equipped models.

One hundred fifty-one vehicles were recruited from the I/M lane in Mesa, AZ during the summer of 1996, and their 24 hour diurnal emissions were measured in a variable temperature SHED (VT-SHED). The fleet selection included the earliest applications of evaporative emission control, and later technologies that had at least 5 years of exposure. Model years 1971 through 1991 were tested. Fifty-three percent of the sample tested had daily emissions of more than 10 grams. Five of the 151 were over 50 grams per day, and had significant liquid leaks. Twenty-six (17%) of the vehicles had emissions exceeding one gram per hour. Thirty-two of the 151 tested (21%) had identifiable liquid leaks. Carburetor systems had higher emissions than fuel injection systems. The highest emitters had resting losses of more than 0.8 g/hr. These eight highest emitters were considered outliers for the purposes of general analysis, and were not used, as is noted in the report.

The requirement to meet more stringent emission standards has focused attention on the effects of gasoline sulfur on automotive emissions. Numerous studies have shown that three-way catalyst performance is severely inhibited by sulfur. A literature review of laboratory studies on the interaction of sulfur with automotive catalyst components provides the basis for understanding impacts on catalyst activity under the variety of conditions encountered in vehicle operation. Under stoichiometric and rich conditions, SO2 formed during combustion is dissociatively adsorbed on platinum group metal surfaces to form strongly bound Sad. Sulfur inhibition results from both physical blockage and electronic effects of Sad, such that low coverage of Sad results in disproportionately higher levels of reaction site blockage. This is responsible for the nonlinear effects observed with increasing fuel sulfur level.

The oxidation of surrogate diesel fuels composed of mixtures of three pure hydrocarbons with and without their cetane numbers chemically enhanced using 2-ethylhexyl nitrate (2-EHN) is studied in a variable pressure flow reactor over a temperature range 500 - 900 K, at 12.5 atmospheres and a fixed reaction time of 1.8 sec. Changes in both low temperature, intermediate temperature, and hot ignition chemical kinetic behavior are noted with changes in the fuel cetane number. Differences appear in the product distribution and in heat release generated in the low and intermediate temperature regimes as cetane number is increased. A chemically enhanced cetane fuel shows nearly identical oxidation characteristics to those obtained using pure fuel blends to produce the enhanced cetane value. The decomposition chemistry of 2-EHN was also studied. Pyrolysis data of 10% 2-EHN in n-heptane and toluene are reported.

Government-industry partnerships are necessary for small businesses to successfully launch new and innovative ideas into the market place. Small businesses, the cornerstone for economic job creation, expansion and retention, is hampered with the need to fund new and innovative technologies from profits which generally occur in a cyclic manner. This cyclic funding leads to ramp ups and development during profitable years, and delays and abeyance during years of downturn. Government-industry partnerships directly addresses this problem by offering funding assistance in the form of resources eliminating the “peaks and valleys” of development. This paper will detail a case study of this type of assistance.