Development of a Low-Speed Two-Stroke Direct-Injection Snowmobile for Use in the Clean Snowmobile Challenge and National Parks

摘要

The University of Idahos entry into the 2011 SAE Clean Snowmobile Challenge (CSC) was a direct-injection (DI) two-stroke powered snowmobile modified to use blended ethanol fuel. The exact composition was unknown prior to the competition. The modulated and battery-less direct-injection system used to decrease exhaust emissions and improve fuel economy maintained near stock power output of the engine. Noise from the engine compartment was reduced by custom placement of sound absorbing materials. A muffler was designed to reduce exhaust noise but proved to limit engine performance and was not used. To further reduce exhaust emissions a catalyst was incorporated into the stock muffler. Pre-competition testing had the snowmobile entering the 2011 SAE CSC competition weighing 535 lbs (243 kg) wet, achieving 21.00 mpg (8.93 km/L) running on blended ethanol fuel, with an EPA five mode emissions test score of 177, and a J-192 sound magnitude score of 80 dBA.