AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Impact of Natural Gas Fuel Composition on PM Mass, Number, and Size Distribution from Heavy-duty Vehicles
MARYAM HAJBABAEI, Zhongqing Zheng, Thomas D. Durbin, Kent C. Johnson, J. Wayne Miller, David R. Cocker III, Georgios Karavalakis, University of California, Riverside
Abstract Number: 544 Working Group: Combustion
Abstract Natural gas (NG) use as an alternative transportation fuel is expanding in recent years. Natural Gas Vehicles (NGVs) are generally believed to produce low emissions of non-methane hydrocarbons (NMHC), carbon monoxide (CO), oxides of nitrogen (NOx), and particulate matter (PM). In California, the use of natural gas is increasing predominantly due to expanded power and home heating needs. With increasing demand for natural gas and liquefied natural gas (LNG), a wider range of sources is needed from new producing fields under development in the western US and new local sources of natural gas.
In this study, the impacts of natural gas composition on criteria and toxic emissions are evaluated for NGVs. Three heavy-duty vehicles were tested on a heavy-duty chassis dynamometer. Two transit buses, with 2009 Cummins ISL-G 8.9 L and 2003 John Deere 8.1L 6081H engines, respectively, were tested on the Central Business District (CBD) test cycle. A waste hauler truck with a Cummins 8.3L C Gas Plus engine was tested on the William H. Martin (WHM) refuse truck cycle. A total of six or seven blends including two gases representative of Texas and Rocky Mountain Pipeline Gases, a Peruvian LNG, a Middle East LNG-Untreated with high Wobbe number (above 1400), two gases representative of those located within the state that have low methane number as well as varying hydrocarbon compositions, and a CNG blend produced from an LNG fuel tank with similar properties to the first two gases were used. The results of PM mass, number, and size distribution for these tests will be presented here. In general, PM mass was very low for all the three vehicles. Some fuel composition effect was observed on particle number and size distribution, which was mainly due to hydrocarbon content of the blends.