External Flow Analysis of a Truck for Drag Reduction

Abstract

Aerodynamics of trucks and other high sided vehicles is of significant interest in reducing road side accidents due to wind loading and in improving fuel economy. Recognizing the limitations of conventional wind tunnel testing, considerable efforts have been invested in the last decade to study vehicle aerodynamics computationally. In this paper, a three-dimensional near field flow analysis has been performed for axial and cross wind loading to understand the airflow characteristics surrounding a trucklike bluff body. Results provide associated drag for the truck geometry including the exterior rearview mirror. Modifying truck geometry can reduce drag, improving fuel economy.

Wind‐Drag Estimation in a Traffic Accident Involving a Motor Scooter and a Tractor–Trailer

“…For simplicity, the computational domain was modeled for a tractor–trailer fixed to the ground under a steadily passing airflow corresponding with the speed of the tractor–trailer. In previous numerical studies on the aerodynamics of heavy trucks or tractor–trailers, researchers used a full‐scale tractor–trailer or truck model and considered an asymmetrically shaped tractor–trailer (3), the cross‐wind (7), and unsteady airflow around the tractor–trailer (5,9,12), which result in asymmetric flow conditions for the tractor–trailer. Assuming that the tractor–trailer has a symmetric geometry with respect to the lateral direction and that air flows uniformly along the longitudinal direction of the tractor–trailer at the inlet boundary condition, a symmetric airflow condition results.…”

“…The first group focuses on drag force reduction to improve fuel economy. Here, the aerodynamics of vehicles have been studied by numerical analyses using computational fluid dynamics or wind tunnel experiments (3)(4)(5)(6). The second group focuses on the effect of wind or vehicle-induced airflow on vehicle stability or external objects such as pedestrians or other vehicles (7)(8)(9)(10)(11)(12)(13).…”

“…Accordingly, half the tractor-trailer was modeled in this study for simplicity. The j-e turbulent model, which provides computational accuracy (3)(4)(5)7,9,12), was used for the airflow analysis. The j-e turbulent model uses the gradient diffusion hypothesis to relate the Reynolds stresses to the mean velocity gradients and the turbulent viscosity.…”

Computational Investigation of Aerodynamic Characteristics and Drag Reduction of a Bus Model

“…Roy and Srinivasan [2] studied the aerodynamics of trucks and other high-sided vehicles that are of significant interest in reducing road accidents due to wind loading and in improving fuel economy. They concentrated on the associated drag due to the exterior rear-view mirrors.…”

Investigation of Modified Profile of Heavy Commercial Vehicle to Prune Aerodynamic Drag.

“…These devices collectively reduced the drag by 30%. Subrata Roy & Pradeep Srinivasan [7] tested the truck and other high sided vehicles without and with different deflector. Cheng Jing & Wu Yun Zhu [8] studied different aerodynamic drag reduction devices (wind deflector & dome) for heavy commercial vehicle.…”