Eddy-resolving Simulations of the Notchback DrivAer' Model: Influence of Underbody Geometry and Wheels Rotation on Aerodynamic Behaviour Technical University of Darmstadt

Format:

Conference/Event

Author/Creator:

Jakirlic, Jakirlic, author.

Contributor:

Basara, Branislav

Hanssmann, Daniel

Kutej, Lukas

Tropea, Cameron

Conference Name:

SAE 2016 World Congress and Exhibition (2016-04-12 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2016

Summary:

The present work deals with a computational study of a DrivAer' car model, the rear-end shape of which corresponds to the Notchback configuration (Heft and others [1] and Heft [2]). The study investigates the effects of the underbody geometry and wheel rotation on the aerodynamic performance. The configurations with detailed and smooth underbody as well as with stationary and rotating wheels are considered. The computational model applied relies on a VLES (Very Large Eddy Simulation) formulation, Chang and others [3]. The residual turbulence related to the VLES framework is presently modelled by a RANS-based (Reynolds-Averaged Navier-Stokes), four-equation (D(k,,ζ, f)/Dt) near-wall eddy-viscosity model, Hanjalic and others [4]. In addition to the equations governing the kinetic energy of turbulence (kus) and its dissipation rate (us), it solves a transport equation for the quantity , representing a key parameter, as it models the velocity scale in the expression for the corresponding turbulence viscosity. In addition to VLES, all considered flows are simulated within both RANS and Unsteady RANS (URANS) frameworks using the same background model formulation representing the constituent of the VLES method. Whereas the "k--ζ-f" model describes fully-modelled turbulence within the RANS/URANS method, it relates to the unresolved sub-scale turbulence within the VLES framework (the relevant quantities are denoted by the subscript us'). Unlike the RANS/URANS method, the VLES method is capable of capturing the spectral dynamics of turbulence to an extent complying with the underlying grid resolution. Accordingly, the superiority of the VLES method is especially visible at the computed evolution of the aerodynamic coefficients, agreeing reasonably well with the experimental database

Notes:

Vendor supplied data

Publisher Number:

2016-01-1602

Access Restriction:

Restricted for use by site license