Search Results

This work presents the autoignition delay time characteristics of methane and natural gas under simulated diesel engine conditions. A constant-volume combustion vessel is used for the experiments. Results are presented for the pressure and temperature ranges of 5 to 55 atm and 600 to 1700 K, respectively. Comparisons are then made with autoignition data for methanol, ethanol, isooctane, and n-cetane. Three major trends are observed. First, there is little effect on the autoignition delay time of natural gas as the vessel pressure is increased from 5 to 55 atm. Second, there is a slight decrease in the autoignition delay time of methane-ethane gas mixtures as the concentration of ethane is increased. Third, the autoignition delay time of natural gas is strongly dependent on temperature and continually decreases with increasing temperature.

This paper describes the design strategy followed to modify a 1998 Polaris Indy Trail [1] as a part of the University of Waterloo's Team Eco-Snow's participation in the Clean Snowmobile Challenge 2000. The team's objectives are to engineer a clean, quiet snowmobile that provides recreational users with a more environmentally friendly vehicle while maintaining a snowmobile that performs on par with current production snowmobiles. The design strategy followed includes the selection of a liquid-cooled engine and subsequent modifications completed to improve the combustion process, the implementation of catalytic converters in the exhaust, and the incorporation of an improved silencer. Less innovative but somewhat overlooked strategies, such as proper carburetor tuning, are also discussed. The completed modifications are reliable and fairly inexpensive, considering the benefits provided.