title: Method for modeling driving cycles, fuel use, and emissions for over snow vehicles.
abstract: As input to a winter use plan, activity, fuel use, and tailpipe exhaust emissions of over snow vehicles (OSV), including five snow coaches and one snowmobile, were measured on a designated route in Yellowstone National Park (YNP). Engine load was quantified in terms of vehicle specific power (VSP), which is a function of speed, acceleration, and road grade. Compared to highway vehicles, VSP for OSVs is more sensitive to rolling resistance and less sensitive to aerodynamic drag. Fuel use rates increased linearly (R2>0.96) with VSP. For gasoline-fueled OSVs, fuel-based emission rates of carbon monoxide (CO) and nitrogen oxides (NOx) typically increased with increasing fuel use rate, with some cases of very high CO emissions. For the diesel OSVs, which had selective catalytic reduction and diesel particulate filters, fuel-based NOx and particulate matter (PM) emission rates were not sensitive to fuel flow rate, and the emission controls were effective. Inter vehicle variability in cycle average fuel use and emissions rates for CO and NOx was substantial. However, there was relatively little inter-cycle variation in cycle average fuel use and emission rates when comparing driving cycles. Recommendations are made regarding how real-world OSV activity, fuel use, and emissions data can be improved.
authors.affiliation: Department of Civil, Construction, and Environmental Engineering, North Carolina State University , Campus Box 7908, Raleigh, North Carolina 27695-7908, United States.
authors.forename: Jiangchuan
authors.initials: J
authors.lastname: Hu
authors.forename: H Christopher
authors.initials: HC
authors.lastname: Frey
authors.forename: Gurdas S
authors.initials: GS
authors.lastname: Sandhu
authors.forename: Brandon M
authors.initials: BM
authors.lastname: Graver
authors.forename: Gary A
authors.initials: GA
authors.lastname: Bishop
authors.forename: Brent G
authors.initials: BG
authors.lastname: Schuchmann
authors.forename: John D
authors.initials: JD
authors.lastname: Ray
mesh_terms: D002248:Carbon Monoxide / Q000032:analysis; D005742:Gasoline; D007700:Kinetics; D016014:Linear Models; D008962:Models, Theoretical; D009589:Nitrogen Oxides / Q000032:analysis; D015541:Off-Road Motor Vehicles; D052638:Particulate Matter / Q000032:analysis; D012914:Snow; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D005742:Gasoline; D009589:Nitrogen Oxides; D052638:Particulate Matter; D001335:Vehicle Emissions; D002248:Carbon Monoxide