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This paper describes the development of a CVS compatible sampling system for automotive sulfate emissions. The design resulted from a consensus of ideas from EPA and industry. The system can be used with either a positive displacement pump or critical flow venturi CVS. A mist generator was developed to quantitatively inject sulfuric acid into the tunnel. While sulfate losses were acceptable using the mist generator, with actual automotive exhaust sulfate losses were much higher. The reasons for these losses were investigated. Sulfate losses in the tubing between the car and sulfate tunnel were also investigated.

Exhaust heat utilization for internal combustion engines has centered around turbosupercharging in recent years, neglecting the promising field of compounding a piston engine with a gas turbine in which, unlike turbocharging, turbine power is fed back to the engine crankshaft. The piston engine can cope with high gas pressure and temperature, whereas the gas turbine can efficiently utilize the energy at relatively low pressure and temperature and large volume flows. By compounding, this-piston engine will handle the high pressure, high temperature phase of the combustion cycle and extend the expansion ratio of the gases to atmospheric pressure by completing the low pressure, low temperature phase in the gas turbine. The marriage of the two engines will result in an outstanding power package with the highest thermal efficiency possible.

REDSOD, an acronym for Repetitive Explosive Device for Soil Displacement, utilizes the energy generated within a combustion chamber by the combustion of compressed air and a hydrocarbon fuel to displace and move soil or material. An integral wedge-shaped base shoe with a large exhaust opening in its top surface is pushed into a soil overburden at depths up to 5 ft or more by a transporting vehicle. When the combustion chamber pressure has reached a maximum value, the hot, high pressure gases are released through the exhaust opening under the soil overburden. The soil is disaggregated and displaced up and out of the excavation. Deflectors can turn the direction of the soil's trajectory to deliver it to one side of the excavation. A greatly increased productivity per unit of equipment is possible over conventional earthmoving means.

Changing fuel quality, increasingly stringent exhaust emission standards, demands for higher efficiency, and the trend towards higher specific output, all contribute to the need for a better understanding of the ignition process in diesel engines. In addition to the impact on the combustion process and the resulting performance and emissions, the ignition process controls the startability of the engine, which, in turn, governs the required compressions ratio and several of the other engine design parameters. The importance of the ignition process is reflected in the fact that the only combustion property that is specified for diesel fuel is the ignition delay time as indicated by the cetane number. The objective of the work described in this paper was to determine the relationship between the ignition process as it occurs in an actual engine, to ignition in a constant volume combustion bomb.

A heavy duty (150 kW) diesel engine was tested to determine operational problems while running on minimally processed synthetic fuels. A reference No. 2 diesel fuel was compared with liquid products derived from shale, tar sands, and coal. Information on the engine setup and test procedure is presented. The test results include engine power, thermal efficiency, ignition delay, gaseous and particulate emissions, smoke opacity, cylinder pressure, and heat release data. Cold start data at 0°C and −20° C and idle deposit test results are also presented. These data should help to determine future engine modifications to enhance synfuel engine performance.

A gasoline direct injection engine was operated at elevated EGR levels over a significant portion of the performance map. The engine was modified to use both cooled and un-cooled EGR in high pressure loop and low pressure loop configurations. The addition of EGR at low and part load was shown to decrease NO and CO emissions and to reduce fuel consumption by up to 4%, primarily through the reduction in pumping losses. At high loads, the addition of EGR resulted in higher fuel consumption benefits of 10-20% as well as the expected NO and CO reductions. The fuel economy benefit at high loads resulted from a decrease in knock tendency and a subsequent improvement in combustion phasing as well as reductions in exhaust temperatures that eliminated the requirement for over-fuelling.

A number of laboratory-scale test methods are available to predict the effects of fuel lubricity on injection system wear. Anecdotal evidence exists to indicate that these methods produce poor correlation with pump wear, particularly for fuels that contain lubricity additives. The issue is further complicated by variations in the lubricity requirements of full-scale equipment and the test methodologies used to evaluate the pumps. However, the cost of performing full-scale equipment testing severely limits the quantity of data available for validation of the laboratory procedures at any single location. In the present study, the technical literature was reviewed and all previously published data was combined to form a single database of 175 pump stand results. This volume of data allows far more accurate statistical analysis than is possible with tests performed at a single location. The results indicate differences in the effectiveness of the standardized laboratory-scale methods.

Particle number concentrations and size distributions were measured for the diluted exhaust of a 1991 diesel engine during the US FTP transient cycle for heavy-duty diesel engines. The engine was operated on US 2-D on-highway diesel fuel. The particle measurement system consisted of a full flow dilution tunnel as the primary dilution stage, an air ejector pump as the secondary dilution stage, and an electrical low pressure impactor (ELPI) for particle size distribution measurements. Particle number emission rate was the highest during the Los Angeles Non Freeway (LANF) and the Los Angeles Freeway (LAF) segments of the transient cycle. However, on brake specific number basis the LAF had the lowest emission level. The particle size distribution was monomodal in shape with a mode between 0.084 μm and 0.14 μm. The shape of the size distribution suggested no presence of nanoparticles below the lower detection limit of the instrument (0.032 μm), except during engine idle.

A typical automotive catalytic converter is constructed with a ceramic substrate and a steel shell. Due to a mismatch in coefficients of thermal expansion, the steel shell will expand away from the ceramic substrate at high temperatures. The gap between the substrate and shell is usually filled with a fiber composite material referred to as “mat.” Mat materials are compressed during assembly and must maintain an adequate pressure around the substrate under extreme temperature conditions. The container deformation measurement procedure is used to determine catalytic converter shell expansion during and after a period of hot catalytic converter operation. This procedure is useful in determining the potential physical durability of a catalytic converter system, and involves measuring converter shell expansion as a function of inlet temperature. A post-test dimensional measurement is used to determine permanent container deformation.

For many years the SAE No. 2 friction machine has been used to measure the coefficient of friction obtained through the interaction of fluid, steel and clutch material. In addition, by forcing energy through the wetted clutch-steel interface and measuring the decay of the coefficient of friction over time, the durability of the materials and fluids can be determined. This paper discusses the use of a numerical computer model to duplicate SAE No. 2 data. The inputs for this model include test stand geometry and physical properties as well as output from a low velocity friction apparatus (LVFA). The LVFA uses a small disc of friction material, a small disc of steel material, and a small sample of fluid to generate a coefficient versus speed curve (m vs v). It was found that torque traces and speed traces generated by this model correlate well with actual SAE No. 2 data. THERE ARE SEVERAL REASONS for creating this model.

This paper will overview current production manual, automatic, and continuously variable transmission (CVT) efficiencies and efficiency variations across the industry. For automatic transmissions, efficiencies associated with the pump and the gearbox components will be highlighted along with areas for improvements. Efficiencies associated with various types of pumps such as internal-external, gerotor, hypocycloidal, and variable displacement will be compared. For CVT's a comparison of efficiencies for belt type and toroidal types will be provided, along with an examination of external-external and variable displacement type ball pumps.

Next generation vehicles are under environmental and economic pressure to reduce emissions and increase fuel economy, while maintaining the same ride and performance characteristics of present day combustion engine automobiles. This has prompted researchers to investigate hybrid vehicles as one possible solution to this challenge. At Southwest Research Institute (SwRI), a unique parallel hybrid drivetrain was designed and prototyped. This hybrid drivetrain alleviates the disadvantages of series hybrid drivetrains by directly coupling the driving wheels to two power sources, namely an engine and an electric motor. At the same time, the design allows the engine speed to be decoupled from the vehicle speed, allowing the engine to operate at its most efficient state. This paper describes the drivetrain, its components, and the test stand that was assembled to test the parallel hybrid drivetrain.

The presented work describes how spark calorimeter testing was used for parametric study and secondary circuit model calibration. Tests were conducted at different pressures, sparkplug gaps and supplied primary energies. The conversion efficiency increases and the spark duration decreases when the gas pressure or the sparkplug gap size is increased. Both gas pressure and sparkplug gas size increase the positive column voltage which represents part of the electrical energy delivered to the gas. The opposite direction occurs when the supplied primary energy is increased. The testing results were then used to calibrate the secondary circuit model which consisted of the sparkplug, the sparkplug gap and the secondary wiring. A step-by-step method was used to calibrate the three constants of the model to match the calculated delivered energy with test data during arc / glow phase.