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The Pennsylvania State University Advanced Vehicle Team (PSUAVT) is one of sixteen collegiate teams across North America participating in the EcoCAR 2: “Plugging In to the Future” competition. The PSUAVT designed and implemented a series plug-in hybrid electric vehicle (PHEV) for this competition. This architecture allows the vehicle to operate as a pure electric vehicle until the energy storage system (ESS) state of charge (SOC) is depleted. The auxiliary power unit (APU) then supplements the battery to extend range beyond that of a purely electric vehicle. To implement this design concept, the PSUAVT re-engineered a General Motors (GM) donated 2013 Chevrolet Malibu to house an electric traction motor, high capacity lithium-ion battery pack, and APU consisting of a low-displacement engine fueled by 85% ethanol/15% gasoline (E85) mixture and an electric generator.

Limited technical studies to speciate particulate matter (PM) emissions from gasoline fueled vehicles have indicated that the lubricating oil may play an important role. It is unclear, however, how this contribution changes with the condition of the lubricant over time. In this study, we hypothesize that the mileage accumulated on the lubricant will affect PM emissions, with a goal of identifying the point of lubricant mileage at which PM emissions are minimized or at least stabilized relative to fresh lubricant. This program tested two low-mileage Tier 2 gasoline vehicles at multiple lubricant mileage intervals ranging from zero to 5000 miles. The LA92 cycle was used for emissions testing. Non-oxygenated certification fuel and splash blended 10% and 20% ethanol blends were used as test fuels.

With the increasing use of modern, EGR-equipped, heavy-duty diesel engines and the use of lower sulfur and alternate fuels, such as biodiesel, lubricants are being exposed to a range of different compositions of acids. To complement the traditional detergent bases, todays lubricants have evolved to include a higher proportion of basic materials from amine-derived sources to aid in oxidation and soot control. This paper explores the impact of the different sources of acids, some of the issues they create and how they can be addressed, exemplified in a prototype CJ-4 lubricant formulation.

Ethanol-gasoline blends are widely understood to present certain technical challenges to engine operation. Despite widespread use of fuels ranging from E5 (5% ethanol in gasoline) in some European countries to E10 (10% ethanol) in the United States to E100 (100% ethanol; “alcool”) in Brazil, there are certain subjects which have only anecdotally been examined. This paper examines two such issues: the effect of ethanol on intake valve deposits (IVD) and the impact of fuel additive on filter plugging (a measure of solubility). The effect of ethanol on IVD is studied along two lines of investigation: the effect of E10 in a multi-fuel data set carried out in the BMW 318i used for EPA and CARB certification, and the effect of varying ethanol content from 0% to 85% in gasoline carried out in a modern flex-fuel vehicle.

Experiments were conducted with a commercially available six-cylinder, 4-valves per cylinder, turbocharged, direct injection (DI) diesel engine. The engine was operated with low sulfur diesel fuel, ultra low sulfur diesel fuel and two other blends, low sulfur diesel fuel with 20 wt.% biodiesel and ultra low sulfur diesel fuel with 20 wt.% biodiesel, to investigate the effect of the base fuels and their blends on combustion and emissions. Combustion analysis, particulate matter emissions and exhaust gas composition (CO, NOX and total hydrocarbons) were determined at eight steady-state operating conditions according to the AVL 8-Mode test protocol. Combustion analysis showed at high load conditions a retarded start of injection, an earlier start of combustion and a lower premixed burn peak with ultra low sulfur diesel fuel. Mode averaged NOX emissions decreased with ultra low sulfur diesel fuel and biodiesel blends compared to low sulfur diesel fuel.

Characteristics of E diesel, a fuel blend of diesel fuel and ethanol, are considered in a matrix of tests. One characteristic of particular concern and a subject of this investigation is that of stability. Methods to evaluate stability are looked at and compared in light of the potential for distillate and ethanol to separate under certain conditions. The quality of the fuel blend is enhanced by the use of enabling additives to ensure stability which necessitates development of a standard for assessment of the quality of stability. The properties of various base diesel fuels and their influence on stability are also studied. Other key characteristics are evaluated including viscosity, pour point, and oxidative stability.

The search for alternative energy sources, particularly renewable sources, has led to increased activity in the area of ethanol blended diesel fuel, or E diesel. E diesel offers potential benefits in reducing greenhouse gases, reducing dependence on crude oil and reducing engine out emissions of particulate matter. However, there are some concerns about the use of E diesel in the existing vehicle fleet. One of the chief concerns of the use of E diesel is the affect of the ethanol on the lubricating properties of the fuel and the potential for fuel system wear. Additive packages that are used to formulate E diesel fuels can improve fuel lubricity and prevent abnormal fuel system wear. This work studies the lubricity properties of several E diesel blends and the diesel fuels that are used to form them. In addition to a variety of bench scale lubricity tests, injector pump tests were performed as an indicator of long term durability in the field.

A new gas phase kinetic model using Westbrook's gas phase n-heptane model and Frenklach's soot model was constructed. This model was then used to predict the impact on PAH formation as an indices of soot formation on ethanol/diesel fuel blends. The results were then compared to soot levels measured by various researchers. The ignition delay characteristics of ethanol were validated against experimental results in the literature. In this paper the results of the model and the comparison with experimental results will be discussed along with implications on the method of incorporation of additives and alternative fuels.

The oxidation of 1-butene and n-butane in air at elevated pressure was investigated in a high pressure chemical flow reactor. Results are presented for pressures of 3, 6, and 10 atm, temperatures near 900K, and lean equivalence ratio. Gas samples were analyzed using gas chromatography with aldehydes sampled using a dinitrophenylhydrazine/acetonitrile procedure employing gas chromatography/mass spectrometry analysis. Major common products observed include CO, CH2O, C2H4, C3H6, and CO2. Additional major products included 1,3-C4H6 for 1-butene and 1-C4H8 for n-butane. Fuel conversion was increased with increased pressure, temperature, and equivalence ratio with 1-butene more reactive than n-butane. Large levels of lower molecular weight carbonyls resulted from 1-butene whereas significant amounts of conjugate and lower molecular weight alkenes resulted from n-butane. Trends in product distributions with increasing pressure were successfully accounted for by current autoignition theories.

Considerable development effort has shown that conventional diesel engine lubricating oil specifications do not define the needs for acceptable injector life in methanol-fueled, two-stroke cycle diesel engines. A cooperative program was undertaken to formulate an engine oil-fuel additive system which was aimed at improving performance with methanol fueling. The performance feature of greatest concern was injector tip plugging. A Taguchi matrix using a 100 hour engine test was designed around an engine oil formulation which had performed well in a 500 hour engine test using a simulated urban bus cycle. Parameters investigated included: detergent level and type, dispersant choice, and zinc dithiophosphate level. In addition, the influence of a supplemental fuel additive was assessed. Analysis of the Taguchi Matrix data shows the fuel additive to have the most dramatic beneficial influence on maintaining injector performance.

Raw oils generated by low-temperature coal pyrolysis were chemically characterized and subjected to tests in three diesel engines of different configuration. The coal liquids were tested as blends with conventional No. 2 diesel fuels, the coal liquids being 20-25% by volume. These tests were performed in support of a broader set of studies on the feasibility of using low-temperature pyrolysis to obtain liquid fuel materials from coal that do not require extensive, costly upgrading. Determination of physical and chemical properties of the pyrolysis liquids indicated a higher hydrogen/carbon ratio and lower aromaticity than typical SRC II and EDS middle distillates. Combustion tests were performed in both direct- and indirect-injection engines at three sites. The results were highly variable, the addition of the oil showing no effect on emissions and performance in some cases, reduced emissions on one engine, and increased emissions in other cases.

An experimental program was conducted to determine the effect of burning used lubricating oil mixed with fuel oil in a single cylinder Diesel engine. With increasing fuel costs, the prospect of using alternative fuels increases dramatically. Large quantities of used lubricating oil are currently available and could be used in fuel blends for Diesel engines. The used lubricating oil-fuel oil ratios used in this study were 2.5%, 5%, 10%, and 15% used lubricating oil by volume. The effect of burning these blends on unburned hydrocarbons, carbon monoxide and oxides of nitrogen is reported along with a comparison to baseline values for pure Diesel fuel. Tests were run at 1800, 2400 and 3000 rpm at 1/4, 1/2, 3/4 and full rack positions for each fuel blend. The general condition of wear in the engine along with deposit formation and analysis is reported. The effect of the used lubricating oil on thermal efficiency and BSFC is shown for the blends studied.