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Studies have shown that the magnitude of pollutant emissions (e.g., NO and PM) from diesel engines operating on fatty acid methyl esters (i.e., FAME biodiesel) are related to the fatty acid composition of the triglycerides present in the bio feedstock. Specifically, NO emissions have been shown to increase with increasing levels of unsaturation in the hydrocarbon chain and decrease with increasing carbon chain length; and PM emissions have been shown to decrease with increasing carbon chain length. Little work has been done to date to characterize the pollutant emissions of algae-based FAME, which have far different fatty acid composition than FAME derived from typical vegetable or animal fat feedstocks. Accordingly, the goal of the present study was to characterize the performance and emissions from a diesel engine operating on FAME with fatty acid composition commensurate with that produced from several algal species currently under consideration for wide scale fuel production.

Most studies have shown that biodiesel results in an increase in NOx emissions with respect to petroleum diesel. The complete mechanism behind the NOx increase from biodiesel is not completely understood but evidence suggests that it is caused by differences in both the physical properties and the chemical oxidation mechanisms between biodiesel and petroleum diesel. To date, the contribution to the biodiesel NOx increases related to differences in chemical kinetics has received very little attention. Similarly, the chemical kinetic mechanism responsible for the dramatic decreases in PM emissions from biodiesel is also poorly understood. As a first step in understanding the chemical kinetic mechanisms behind biodiesel NOx and PM processes, appropriate surrogate fuels must be identified that have similar chemical structure (and/or autoignition characteristics) to the long chain methyl esters found in biodiesel.

The New Jersey Department of Transportation (NJDOT) is currently sponsoring a research study at Rowan University to develop strategies for reducing diesel emissions from mobile sources such as school buses and class 8 trucks. This paper presents the results of mobile school bus testing that has been performed to quantify the emission reduction capabilities of various alternative fuels, such as B20/#2 diesel, ultra low sulfur diesel (ULSD), and B20/ULSD, when applied to school buses that are representative of those currently in use in the state of NJ. Three school buses equipped with an International T444E, an International DT466E, and a Cummins 5.9L ISB engine were instrumented and tested at the Aberdeen Test Center at the Aberdeen Proving Grounds in Maryland. Exhaust gas emission measurements were made using a Semtech-D mobile emissions analyzer to measure CO, CO2, NO2, NO, O2, and unburned hydrocarbons, along with a Sensors PM-300 to measure PM.

The New Jersey Department of Transportation (NJDOT) is currently sponsoring a research study at Rowan University to develop strategies for reducing diesel emissions from mobile sources such as school buses and class 8 trucks. This paper presents the results of mobile school bus testing that has been performed to quantify the emission reduction capabilities of various aftertreatment devices. Particulate filters from Johnson Matthey and Lubrizol were tested along with a diesel oxidation catalyst (DOC) from Nett Technologies. Three school buses equipped with a 1997 7.3L International T444E, a 1997 7.6L International DT466E, and a 1996 Cummins 5.9L ISB series engine were instrumented and tested at the Aberdeen Test Center at the Aberdeen Proving Grounds in Maryland. Exhaust gas emission measurements were made using a Sensors Semtech-D to measure CO, CO2, NO2, NO, O2, and HC, along with a Sensors PM-300 to measure particulate matter (PM).

Heavy Duty Diesel Truck (HDDT) drivers are required by law to rest 8 hours for every 10 driving hours. As a consequence, the trucks are idled for long periods of time to heat or cool the cabin, to keep the engine warm, to run electrical appliances, and to refrigerate or heat truck cargo. This idling results in gaseous and particulate emissions, wasted fuel and is costly. Various technologies can be used to replace truck idling, including heaters, auxiliary power units, parking space electrification, and heating and air conditioning units in the parking space. In this paper the results of a life cycle analysis are reported giving the associated emissions savings and ecological burdens of these four technologies compared to truck idling. In this analysis the savings related to reduced engine maintenance and increased engine life are included. The fuel consumed and emissions produced by a truck engine at idle was obtained from experiments performed at Aberdeen Test Center (ATC).

The New Jersey Department of Transportation (NJDOT) is currently sponsoring a research study at Rowan University to develop strategies for reducing diesel emissions from mobile sources such as school buses and class 8 trucks. One such source of diesel emissions results from unnecessary idling of school buses, which is a typical practice that occurs in the mornings to warm up engines and in the afternoon while bus drivers wait to pick up children for their afternoon routes. To quantify emissions and fuel consumption during idling, three school buses equipped with an International T444E, an International DT466E, and a Cummins 5.9L B series engine were instrumented and tested in an environmental chamber. To simulate a wide variety of idling situations, tests were conducted at four different ambient temperatures (20°F, 40°F, 65°F and 85°F) and relative humidity ranging from 37 to 90%.

A steady state mobile test was developed to measure the concentration of breathable particles that can enter the cabin of a school bus. The principles of experimental design were used to identify the experimental conditions for the test and to analyze the data. The design consisted of a series of steady-state tests using a 1992 International school bus. The testing was performed on a closed three mile track at the Army Test Center in Aberdeen, MD. The mass concentrations of particles smaller than 2.5 microns were measured at three locations inside the bus and at the air intake into the engine. The number concentration of particles was measured at the tailpipe. Three factors were varied at three levels in a Box-Benhken design. The steady state speed was set at 5, 30, and 55 mph. A load was applied to the engine with a mobile dynamometer to simulate a 0, 0.67% and 1.33% road grade.

A significant fraction of diesel emissions can be attributed to heavy-duty diesel vehicles at idle conditions during which power is being used for systems such as cabin heating or cooling. Although, a variety of low emission, auxiliary power solutions already exist for HDDV trucks, they are not in wide spread use. Moreover, very little work has been done to date to quantify the total emissions and fuel consumption from truck idling. Accordingly, the U.S. Environmental Protection Agency, in collaboration with the New Jersey Department of Transportation, the U.S. Army Aberdeen Test Center, Oak Ridge National Laboratory and Rowan University has initiated a study to quantify the idling emissions and fuel consumption rates for HDDV trucks. Testing was performed in an environmental chamber on five different class 8 trucks with model years ranging from 1990's to 2001.