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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.

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.

There have been estimates that the solid waste stream of municipal garbage could be converted to 5% of the total electric power requirement. In response to this potential many high capital cost incinerators have been installed around the country during the last two decades. Success has been marginal and many have been prematurely shut down because of technical problems and public concerns about emissions and potentially toxic ash. The alternative is to continue to use landfills, but to capture the methane that is produced by the decay of organic matter for the production of heat and electricity. Several such facilities have been installed in recent years and are demonstrating increasingly favorable operation. The purpose of this project was to research the techniques and technologies that are used to harness landfill gas, along with the related considerations of state and federal regulations and public health concerns from exposing the public to unburned and uncleaned landfill gas.

An experimental study was conducted to investigate methanol autoignition including surface effects. Autoignition temperatures were determined for methanol using spherical, glass, constant volume bombs of various size, in order to assess the effects of changing the vessel surface-to-volume ratio on the minimum autoignition temperature and on the autoignition limits and ignition delays. Autoignition limit diagrams were constructed by determining the autoignition temperature for various methanol/oxygen/nitrogen mixtures. The diagrams were characterized by a minimum autoignition temperature occurring at a particular equivalence ratio, which was typically not stoichiometric. An empirical Arrhenius type expression for ignition delay was also developed and analyzed with respect to surface effects. This model was then compared with models used at higher temperatures.

The autoignition characteristics of ethanol were examined in the 667-743 K temperature range at one atmosphere. A closed static reactor testing facility, of the Le Chatelier type was employed in this study. The autoignition limits for two ethanol concentrations at varied oxygen-nitrogen concentrations are mapped out. At each fuel concentration the minimum autoignition temperature occurred at an equivalence ratio of 0.3. An Arrhenius-type expression for the ignition delay time was developed and yielded a global activation energy of 42.1 kcal/mol. Increases in ethanol and oxygen concentrations cause a decrease in ignition delay time. Ethanol concentrations proved to have a greater effect on the ignition delay times than did oxygen concentrations.

An experimental study was conducted to investigate the autoignition characteristics of methanol. Experimental conditions which were explored included temperatures in the range of 650-800 K, equivalence ratios of 0.2-17.0, 1 atm pressure, and reactor surface-to-volume ratios. S/V, of 0.6 cm−1″ and 0.48 cm−1. The ignition delay times were correlated with initial temperatures, methanol, and oxygen concentrations and fit to an Arrhenius type expression. The analysis resulted in a global activation energy of 55.2 kcal/mol and fuel and oxidizer concentration exponents of −0.98 and −0.13, respectively. Also, autoignition limit diagrams were developed which distinguish the regions of ignition and non-ignition, as well as show the effects of equivalence ratio and surface-to-volume ratio changes on minimum autoignition temperatures.

A hypothetical residential building in Albany, New York with a structure heat loss of 870 Btu/hr-°F is considered. The energy requirements for heating such a house by different systems are investigated employing the bin method and a computer program. The systems whose performance are evaluated are: (1) air-to-air heat pump with electric resistance heating backup, (2) gas furnace, (3) oil furnace and (4) electric resistance baseboard. The yearly energy costs for operating these four systems are estimated and compared. It is found that the natural gas heating is the most economical and electric baseboard heating the most expensive. The heat pump is the second most economical with oil heating being very close third. These relative ratings may change if the cooling needs are taken into account, initial costs are amortized or unit energy costs vary.

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.