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Diesel fuels derived from Fischer-Tropsch processes have a number of beneficial properties, including zero sulfur, high cetane, and near-zero aromatics content. Previous researchers have shown emissions benefits for using these fuels in light and heavy-duty diesel engines. A series of experimental fuels using neat F-T material or blends of F-T material with conventional cracked stocks was tested in diesel engines and produced lower emissions when compared to current diesel fuel. These experimental fuels cover a variety of boiling point ranges, extending from light naphtha to materials that are significantly heavier than conventional diesel fuels. All of the fuels show lower NOx and particulate emissions. F-T material can be used to increase the use of marginal refinery streams as diesel blend stocks and so increase the volume of low emission diesel fuels produced in current refineries.

Fuel cell powered vehicles offer the potential of ultra-low or zero emissions along with very high efficiency. The major practical barrier to wide-spread introduction has been the need to provide hydrogen to the fuel cell. On-board hydrogen storage is not practical at the current time, leading to a large research and engineering effort in developing fuel processors that convert a hydrocarbon fuel such as gasoline, methanol or methane into a hydrogen-rich reformate. A key component of these systems, all of which have multiple catalytic reactors, is the processor response to transient operation that is inherent to vehicle use. This paper reports on a research reactor system designed to measure the transient response of fuel processors, and reports preliminary measurements of transient response for the primary reformer reactor of a gasoline fuel processor.

Fuel cells offer the potential of ultra-low emissions combined with high efficiency. Recent, rapid advances in the past few years in fuel cell technology have resulted in a vast increase in fuel cell research and development directed towards wide spread application in vehicle and stationary power. The PEM (proton exchange membrane) fuel cell proposed for future vehicles requires hydrogen as a fuel. Supplying hydrogen, as either hydrogen gas or a hydrogen-rich reformate, is a critical issue. A large number of fuel sources can be used to provide the hydrogen, each has advantages and disadvantages. For example, hydrogen provides the simplest and easiest on-board system, but requires the largest infrastructure hurdles. Methanol has some advantages in producing usable reformate, but several other issues ranging from performance on cold-start and transients, to acute toxicity and maintaining purity in transport would need to be addressed.

A pseudo-slow motion video system has been used to directly image gasoline transport in the intake system of four engines. Injector spray pattern, location, and timing are all shown to have a strong influence on the wetting and washing of the intake valves. These parameters are strongly correlated with base fuel and additive performance: increasing valve wetting and washing result in better additive performance and lower valve deposit levels.