Experimental and Numerical Investigations of the Base Wake on an SUV 2013-01-0464
With the increase in fuel prices and the increasingly strict
environmental legislations regarding CO₂ emissions, reduction of
the total energy consumption of our society becomes more important.
Passenger vehicles are partly responsible for this consumption due
to their strong presence in the daily life of most people.
Therefore reducing the impact of cars on the environment can assist
in decreasing the overall energy consumption. Even though several
fields have an impact on a passenger car's performance, this
paper will focus on the aerodynamic part and more specifically, the
wake behind a vehicle.
By definition a car is a bluff body on which the air resistance
is for the most part driven by pressure drag. This is caused by the
wake these bodies create. Therefore analyzing the wake
characteristics behind a vehicle is crucial if one would like to
reduce drag. With the recent upgrade of wind tunnels with a moving
belt system, the opportunity has emerged to investigate the flow
field in the wake behind vehicles, matching closer the real on-road
This study investigates experimentally and numerically the wake
behind a passenger car of an SUV type. Three configurations with a
significant change in CD have been chosen for the analysis. Their
wake shape together with their respective closure points have been
analyzed using three planes, namely one x-plane, one y-plane and
Results have shown that the numerical simulations correlate well
with the experiments in wake shape and wake behavior. However in
the chosen configurations they underestimate the wake length. A
distinct interference of the traversing unit presence can be noted
in the experimental results.