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It is now a fairly well established fact that excessive ring and cylinder bore wear can result from the operation of an S. I. engine on neat methanol. The mechanism leading to the excessive wear were investigated using both engine and bench tests. Engine tests using prevaporized superheated methanol indicated that the wear results from reactions between the combustion products and the cast iron cylinder liner, where the presence of liquid methanol in the combustion chamber appears to be an important part of the mechanism. These reactions were investigated using a spinning disc combustor. The spinning disc combustor was used to provide a source of burning methanol droplets which were subsequently quenched on a water-cooled cast iron surface. The condensate formed on the cast iron surface was collected and analyzed for chemical composition. Infrared analysis indicated the presence of large quantities of iron formate, a reaction product of iron and formic acid.

Due to the cost and mobility advantages of diesel-powered mine vehicles over electric vehicles, it is anticipated that the diesel engine will become more widely used in underground mines in this country. Concern has arisen, however, over the impact of diesel exhaust emissions on the air quality in the underground mine environment. A literature search has been conducted to identify known effects of fuel properties on the reduction of diesel exhaust emissions. Reductions can be obtained by optimizing fuel properties and by considering alternative fuels to standard diesel fuel. However, the data base is relatively small and the results highly dependent on engine type and operating conditions. Engine studies on a typical mine diesel are necessary to draw quantitative conclusions regarding the reduction of emissions, especially particulates and NO2 which have not been generally addressed in previous studies.

Hybrids are fuels derived from combinations of different energy sources and which are generally formulated as solutions, emulsions, or slurries. The underlying objective of this program is to reduce the use of petroleum-derived fuels and/or to minimize the processing requirements of the finished hybrid fuels. Several hybrid fuel formulations have been developed and tested in a direct injection single-cylinder diesel engine. The formulations included solutions of ethanol and vegetable oils in diesel fuel, emulsions of methanol and of ethanol in diesel fuel; and slurries of starch, cellulose, and “carbon” in diesel fuel. Based on the progress to date, the solutions and emulsions appear to be viable diesel engine fuels if the economic factors are favorable and the storage and handling problems are not too severe. The slurries, on the other hand, are not to the same point of development as the solutions and emulsions.

A constant volume bomb was used to determine basic combustion characteristics of isooctane, n-heptane, methanol, propane and methane. Results show that the laminar flame velocity of a quiescent homogeneous air/fuel mixture can be derived from pressure-time data in the bomb. The effects of pressure, temperature, and charge dilution on flame velocity and ignition are presented. A thermo-chemical kinetic model accurately predicted concentrations of nitric oxide during combustion and in the burned gas.