Formulae for the Tractive-Energy Requirements of Vehicles Driving the EPA Schedules

A comprehensive analysis of the tractive-energy requirements of the EPA Urban and Highway driving schedules has been made. The results are compact formulae in which the specific tractive energy required to negotiate a schedule is correlated primarily with the ratio of effective aerodynamic frontal area to vehicle mass; the tire rolling resistance coefficients are additional variables. The formulae coefficients permit easy determination of the proportions of the Input energy required for overcoming the aerodynamic and rolling resistances, and for supplying the net powered increases in vehicle kinetic energy, respectively. The specific energy dissipated by braking has also been formulated.