Tehničko veleučilište u Zagrebu · Zagreb

Automobile aerodynamics influenced by airfoil-shaped rear wing

izvorni znanstveni rad

izvorni znanstveni rad

Automobile aerodynamics influenced by airfoil-shaped rear wing

Vrsta prilog u časopisu
Tip izvorni znanstveni rad
Godina 2016
Časopis International journal of automotive technology
Nadređena publikacija International journal of automotive technology
Volumen 17
Svesčić 3
Stranice str. 377-385
DOI 10.1007/s12239-016-0039-4
ISSN 1229-9138
EISSN 1976-3832
Status objavljeno

Sažetak

Computational model is developed to analyze aerodynamic loads and flow characteristics for an automobile, when the rear wing is placed above the trunk of the vehicle. The focus is on effects of the rear wing height that is investigated in four different positions. The relative wind incidence angle of the rear wing is equal in all configurations. Hence, the discrepancies in the results are only due to an influence of the rear wing position. Computations are performed by using the Reynolds-averaged-Navier-Stokes equations along with the standard k-ε turbulence model and standard wall functions assuming the steady viscous fluid flow. While the lift force is positive (upforce) for the automobile without the rear wing, negative lift force (downforce) is obtained for all configurations with the rear wing in place. At the same time, the rear wing increases the automobile drag that is not favorable with respect to the automobile fuel consumption. However, this drawback is not that significant, as the rear wing considerably benefits the automobile traction and stability. An optimal automobile downforce-to-drag ratio is obtained for the rear wing placed at 39 % of the height between the upper surface of the automobile trunk and the automobile roof. Two characteristic large vortices develop in the automobile wake in configuration without the rear wing. They vanish with the rear wing placed close to the trunk, while they gradually restore with an increase in the wing mounting height.

Ključne riječi

automobile aerodynamics ; rear wing ; aerodynamic forces ; steady Reynolds-averaged-Navier-Stokes ; k-ε turbulence model