Fuel usage negatively impacts the environment and is a significant portion of operational costs of moving freight globally. Reducing fuel consumption is key to lessening environmental impacts and maximizing freight efficiency, thereby increasing the profit margin of logistic operators. In this paper, fuel economy improvements of a cab-over style 49T heavy duty Foton truck powered by a Cummins 12-liter engine are studied and systematically applied for the China market.
Most fuel efficiency improvements are found within the vehicle design when compared to opportunities available at the engine level. Vehicle design (improved aerodynamics), component selection/matching (low rolling resistance tires), and powertrain electronic features integration (shift schedule/electronic trim) offer the largest opportunities for lowering fuel consumption.
The powertrain features include Cummins adaptive torque modulation and transmission neutral coasting. 3D CFD (ANSYS Fluent®) was used to carry out external truck aerodynamics study, and Cummins Vehicle Mission Simulation (VMS) was used to study and optimize the powertrain integration features. A system simulation model was developed on a baseline truck and calibrated via on-road testing. An energy study quantified the contribution of aerodynamic and rolling resistance losses. Low rolling resistance tires and improved aerodynamic features were applied along with electronic powertrain features to optimize the truck design based on the analysis.
The optimized truck demonstrated approximately 20% better fuel economy than the baseline truck in the final testing. Coast-down testing and one-dimensional system simulation indicated that low rolling resistance tires, aerodynamic design, and powertrain integration features contributed 6%, 9%, and 5% of fuel economy improvement, respectively.