Spatial and Temporal Investigation of Real World Crosswind Effects on Transient Aerodynamic Drag Losses in Heavy Duty Truck Trailers in the US

Abstract

Spatial and Temporal Investigation of Real World Crosswind Effects on Transient Aerodynamic Drag Losses in Heavy Duty Truck Trailers in the US Bharadwaj Sathiamoorthy Decreasing truck fuel usage and climate change gas production is of national and global importance. This study focuses on large, heavy-duty on-road tractor trailer combinations because of their impact in terms of fuel consumption levels, emissions, and their dominance in freight transportation in the United States, which offers substantial potential to improve efficiency of the transportation sector and reduce emissions. The US Department of Energy completed a study of this topic in 2009, and the EPA and NHTSA are both engaged in regulating truck efficiency. The Energy Information Administration (EIA) reported that more than 50 percent of the total diesel consumed was for transportation and this percentage will increase. With about 65 percent of the total engine-out energy consumed by a typical heavy-duty tractor trailer being spent on overcoming aerodynamic drag at highway speeds (55mph in the USA), improvements to aerodynamic performance offers a substantial avenue for reduction in fuel usage and emissions. Besides being directly related to fuel consumption, emissions, maximum speed and acceleration, aerodynamic phenomena also influence the stability characteristics of road vehicles, and their response to crosswinds. Crosswinds from any directions will affect the drag losses and will cause a significant change in pressure distribution along the truck body. The main objective of this research is to provide a better understanding of the influence of crosswinds on the aerodynamic performance of heavy-duty tractor trailers in the United States.