Search Results

This paper reviews fuel-saving technologies for commercial trailers, provides an overview of the trailer market in the U.S., and explores options for policy measures at the federal level that can promote the development and deployment of trailers with improved efficiency. For trailer aerodynamics, there are many technologies that exist and are in development to target each of the three primary areas where drag occurs: 1) the tractor-trailer gap, 2) the side and underbody of the trailer, and 3) the rear end of the trailer. In addition, there are tire technologies and weight reduction opportunities for trailers, which can lead to reduced rolling resistance and inertial loss. As with the commercial vehicle sector, the trailer market is diverse, and there are a variety of sizes and configurations that are employed to meet a wide range of freight demands.

This analysis is a comprehensive assessment of the fuel-saving technologies and technology packages for three representative diesel HDV types in India: a 40-tonne Gross Vehicle Weight (GVW) tractor-trailer, 25-tonne rigid truck, and a 16-tonne transit bus. These representative vehicle types are modeled after top-selling models in the Indian market based on sales data from fiscal year 2013-14. To model these vehicle types are accurately as possible, the study team acquired detailed engine maps that match the engine models in the respective vehicles and sought input on other vehicle systems from some of the leading Indian HDV manufacturers and suppliers. Using Autonomie as the vehicle simulation platform, the authors investigate the fuel consumption impacts of both individual technologies and combinations of technologies in the following areas: engine, transmission, driveline, aerodynamics, tires, material substitution (i.e., curb weight reduction), and hybridization.

Heavy duty tractor-trailers under freeway operations consume about 65% of the total engine shaft energy to overcome aerodynamic drag force. Vehicles are exposed to on-road crosswinds which cause change in pressure distribution with a relative wind speed and yaw angle. The objective of this study was to analyze the drag losses as a function of on-road wind conditions, on-road vehicle position and trajectory. Using coefficient of drag (CD) data available from a study conducted at NASA Ames, Geographical Information Systems model, time-varying weather data and road data, a generic model was built to identify the yaw angles and the relative magnitude of wind speed on a given route over a given time period. A region-based analysis was conducted for a study on interstate trucking operation by employing I-79 running through West Virginia as a case study by initiating a run starting at 12am, 03/03/2012 out to 12am, 03/05/2012.