Abstract
KEYWORDS
Aerodynamic loads, underhood airflow, underbody drag of vehicle, dimensionless characteristic indicators, optimising methods
ABSTRACT
The aerodynamics loads which are acting on a road vehicle play a significant part concerning the dynamic behaviour of the latter as regards stability, handling, crosswind sensitivity and not lastly upon the fuel consumption and the wind noise. These are the main reasons for what the aerodynamics has succeeded to become one of the most important preambles in designing of the cars in the last decade. The aerodynamic performances of the vehicles are characterised using specific coefficients, dimensionless, nsionless, as CD , (drag coefficient), CD (lift coefficient) a.o. Using of these coefficients as the measure of the state of the art in the vehicle aerodynamics, the continuously progress is possible in this field. As already showed, a method to improve the dynamic behaviour for a car, with a defined shape of the body, is to manage the aerodynamics interaction between the vehicle and the road [1, 4]. In previous study was presented a theoretical method for computing of the drag due to the underhood airflow, respectively the underbody drag Dub . In this study, what represent a companion paper of Benche & Huminic (2004), are emphasised the main factors which having importance on Dub and which may lead to optimising steps with respect to the aerodynamics of vehicles. The study is illustrated by means of a numerical exemplification.