Natural gas as a modern engine fuel: Fuelling strategies, in-cylinder processes, and real-world emissions
Dr. Patrick Kirchen
Assistant Professor, Department of Mechanical Engineering
University of British Columbia
When: November 22, 2018 | 1 PM
Where: CEME 2202 | 6250 Applied Science Lane
Abstract: Natural gas as an engine fuel is a potential approach to reduce the environmental impact of transportation applications where electrification is not (yet) possible. It can provide reductions in CO2 and toxic emissions, as well as reduce the total cost of operation; however, these benefits must also consider any CH4 emissions. Unburned CH4 is a potent greenhouse gas and its emission can result in a higher global warming potential, relative to existing fuelling technologies. Here we consider strategies for compression ignition natural gas engines using a combination of in-cylinder imaging, probe based diagnostics, and emission and heat release measurements in research engines, as well as field studies of in-use natural gas engines on a marine vessel. Pilot ignited premixed and direct injected natural gas fuelling strategies are evaluated in a new optical engine facility using natural luminosity, OH* chemiluminescence, and pyrometric imaging to elucidate fuel conversion mechanisms and the influence of key fuel injection parameters. For both fuelling strategies, subtle changes in the injection schedule can significantly impact the fuel conversion mechanism and the engine performance. The implications of the fuelling strategy are further assessed by characterizing the in-use CH4 emissions from a natural gas fuelled marine vessel using a new wavelength modulation spectroscopy system. Through a combination of engine control and vessel operation modifications, strategies are proposed and implemented to reduce the CH4 emissions and global warming potential of the vessel.
Biography: Pat Kirchen is an assistant professor in the Department of Mechanical Engineering. His research is focussed on reducing the environmental impact of practical energy conversion systems, with current applications including: characterization and optimization of fuelling strategies for internal combustion engines using natural gas and other alternative fuels (bio-oil, hydrogen); development of high speed emission sensors, and; experimental and numerical investigations of ion transport membranes for gas separation and fuel reforming. Pat received his BSc and MSc from the University of Alberta and PhD from the ETH Zurich (2009), all in Mechanical Engineering. Prior to coming to UBC he was a postdoctoral associate and research scientist at the Massachusetts Institute of Technology (2009-2012).