Search Results

In urban areas, particulate emission from diesel engines is one of the pollutants of most concern. As a result, particulate emission control from urban bus diesel engines using particle filter technology is being evaluated at several locations in the US. A project entitled, “Clean Diesel Vehicle Air Quality Project” has been initiated by NY City Transit under the supervision of NYSDEC and with active participation from several industry partners. Under this program, 25 NY City transit buses with DDC Series 50 engines have been equipped with continuously regenerating diesel particulate filter systems and have been operating with ultra low sulfur diesel (< 30 ppm S) in transit service in Manhattan since February 2000. These buses were evaluated over a 9 month period for operations, maintainability and durability of the particulate filter.

Particulate emission from diesel engines is one of the most important pollutants in urban areas. As a result, particulate emission control from urban bus diesel engines using particle filter technology is being evaluated at several locations in the US. A project entitled “Clean Diesel Demonstration Program” has been initiated by NY City Transit under the supervision of NY State DEC and with active participation from several industrial partners. Under this program, several NY City transit buses with DDC Series 50 engines have been equipped with continuously regenerating diesel particulate filter system and are operating with ultra low sulfur diesel (< 30 ppm S) in transit service in Manhattan since February 2000. These buses are being evaluated over a 8-9 month period for operations, maintainability and durability of the particulate filter.

A significant deterioration in low temperature pumpability properties (as measured by the mini-rotary viscometer; MRV) was observed in certain commercial-quality engine oils in a taxi field test program. A detailed investigation demonstrated that contamination by carry-over of the factory fill oil in combination with oil aging was the cause of the marked deterioration in low-temperature pumpability properties; no evidence of new oil incompatibility was observed using industry-standard test procedures. A subsequent investigation identified a number of commercial ILSAC GF-2 quality engine oils which also caused large MRV viscosity increases when added in concentrations as low as 1 wt% to used engine oils. A root-cause evaluation established that low concentrations of certain viscosity index improvers caused large MRV viscosity increases when added to used oils.

The Coordinating Research Council conducted a program to measure the reversibility of fuel sulfur effects on emissions from California Low Emission Vehicles (LEVs). Six LEV models were tested using two non-oxygenated conventional Federal fuels with 30 and 630 ppm sulfur. The following emission test sequence was used: 30 ppm fuel to establish a baseline, 630 ppm fuel, and return to 30 ppm fuel. A series of emission tests were run after return to 30 ppm to ensure that emissions had stabilized. The effect of the driving cycle on reversibility was evaluated by using both the LA4 and US06 driving cycles for mileage accumulation between emission tests after return to 30-ppm sulfur fuel. The reversibility of sulfur effects was dependent on the vehicle, driving cycle, and the pollutant. For the test fleet as a whole most but not all of the sulfur effects were reversible.

From 1995 to 1997, the Coordinating Research Council (CRC) conducted a cold-start driveability program to evaluate the behavior of lower volatility fuels at cold, intermediate, and warm ambient temperatures. The program used 135 vehicles to evaluate 87 hydrocarbon, MTBE blended, and ethanol blended fuels. Evaporative driveability index equations (EDIs) were developed using the test design fuel variables (E158°F, E200°F, E300°F), and three other variable sets: (E158°F, E250°F, E330°F), (T10, T50, T90), and (E70°C, E100°C, E140°C). The models that best fit the data contained oxygenate offsets. Overall, the best indices are the E70°C, E100°C, E140°C equation and the DI equation with offsets.

Hundreds of components on the frame of an airplane are lubricated with grease. Since the performance of such components is critical, a number of grease specifications have been written to cover airframe grease applications. The proliferation of different airframe grease specifications complicates the maintenance of mixed fleets of airplanes and increases the opportunities for misapplication of grease. In the past decade, efforts have been made to reduce the number of greases required for airframe lubrication by enhancing the multipurpose nature of the relevant grease specifications. This paper compares four specifications that are used to specify airframe greases and describes a multipurpose grease which meets two of the major airframe grease specifications.