Achievement of Low Emissions by Engine Modification to Utilize Gas-to-Liquid Fuel and Advanced Emission Controls on a Class 8 Truck

Abstract

A 2002 Cummins ISM engine was modified to be optimized for operation on gas-to-liquid (GTL) fuel and advanced emission control devices. The engine modifications included increased exhaust gas recirculation (EGR), decreased compression ratio, and reshaped piston and bowl configuration. The emission control devices included a deNO x filter and a diesel particle filter. Over the transient test, the emissions met the 2007 standards.In July 2004, the modified engine was installed into a Class 8 tractor for use by a grocery fleet. Chassis emission testing of the modified vehicle was conducted at the National Renewable Energy Laboratory's (NREL) Renewable Fuels and Lubricants (ReFUEL) facility. Testing included hot and cold replicate Urban Dynamometer Driving Schedule (UDDS) and New York Composite (NYComp) cycles and several steady-state points. The objective of the testing was to demonstrate the vehicle's with the modified engine.Average vehicle NO x emissions from the UDDS cycle were 6.20 g/mi and 4.26 g/mi from cold and hot runs, respectively, with nitrogen dioxide (NO 2 ) emissions ~50% of the total NO x emissions. Over the NYComp cycle, the cold start emissions were 12.75 g/mi and the hot start emissions were 7.74 g/mi. The carbon monoxide (CO), hydrocarbons (HC), and PM emissions were very low, with average PM less than 0.005 g/mile for hot starts over both cycles.The test inertia weight was varied from 46,000 lbs to 63,000 lbs to 80,000 lbs on a random basis for repeated hot-start cycles. The NOx emissions varied from 3 to 5 g/mi over the UDDS cycle and from 6 to 8 g/mi over the NYComp cycle.Steady-state testing was also performed at repeated cruise conditions ranging from 10 to 60 mph. Average NO x emissions on a g/mi basis were the highest for this test matrix at 6.7 g/mi during 10 mph cruise conditions, ~3 g/mi over 20, 30, 40, and 50 mph cruises, and ~1.8 g/mi during 60 mph cruise conditions.The results from this testing showed that the modified engine and emission control systems performed effectively in vehicle operation. The technology performed as expected on two very different test cycles and a range of steady-state speed and load points. The longer-term durability of the technology will be measured after six months with additional chassis testing. NREL/CP

Ignition and combustion characteristics of various biodiesel fuels (BDFs)

“…7 that the reasonable shorter ignition delays were obtained at the temperature range from 700 K to 900 K. That temperature range covers top dead center (TDC) temperatures in the compression ignition engine with direct-injection [25][26][27]. It indicates that acceptable ignition characteristics may be obtained at normal engine conditions.…”

Ignition and Combustion Characteristics of Gas-to-Liquid Fuels for Different Ambient Pressures

“…The advantages of GTL fuel have attracted many researchers to apply GTL fuel for engines and vehicles. − In most papers, the results showed that GTL fuel reduced exhaust gas emissions of carbon monoxide, hydrocarbons, nitrogen oxides, and particulate matter compared to gas-oil (conventional diesel fuel). Normally, the research started from a short-term test, where a diesel engine was switched to run with GTL fuel for collecting the performance and emission data.…”

Effects of Fischer—Tropsch diesel fuel on soot formation processes in a diesel spray flame

“…There have been numerous researches on the combustion and emission characteristics of the FTD-fuelled diesel spray flame, including reports on performance improvements by engine optimization for the FTD fuel [1][2][3][4][5][6][7][8][9]. However, the mechanism of PM reduction in FTD-fuelled diesel engines compared with conventional JIS#2 diesel fuel has not been clearly explained.…”