An Aerodynamic Investigation of an Isolated Stationary Formula 1 Wheel Assembly

Abstract

The flowfield around a 60% scale stationary Formula 1 tire in contact with the ground in a closed wind tunnel at a Reynolds number of 500,000 was computationally examined in order to assess the accuracy of different turbulence modeling techniques and confirm the existence of large scale flow features. A simplified and replica tire model that includes all brake components was tested to determine the sensitivity of the wake to cross flow within the tire hub along with the flow blockage caused by the brake assembly. The results of steady and unsteady Reynolds averaged Navier-Stokes (URANS) equations and a large eddy simulation (LES) were compared with the experimental data. The LES closure and the RANS closure that accounted for unsteadiness with low eddy viscosity (unsteady kω-SST) matched closest to the experimental data both in point wise velocity comparisons along with location and intensity of the strong counter-rotating vortex pair dominating the far wake of the tire.

Computational investigation into the influence of yaw on the aerodynamics of an isolated wheel in free air

“…Results also indicate that as a consequence of these two distinct flows over the top and bottom of the wheel, and their interaction with the wheel side-flow, four distinct and separate vortices are created and convect downstream. The physical mechanisms for the generation of these vortical structures are known to be fundamental to the resulting flow field in several ways (Axerio-Cilies et al, 2012). As is shown in Figure 7(a), the four vortices generated play a significant role in entraining the flow from the top and bottom of the wheel, whereby delaying flow separation and producing a much smaller wake size than would be experienced from larger aspect ratio configurations.…”

On the interaction of a racing car front wing and exposed wheel

“…All gradients were evaluated at the cell centres and a converged solution was deemed to be obtained only when there was negligible variation in the force coefficients with extensive continued iteration. Only steady-state simulations were considered; this remains the preferred approach in industry for reasons of computational expense and real-time limits, despite the obvious propensity for racing car component flowfields (particularly around the wheels) to be highly unsteady (14) .…”

“…Due to the requirements of regulations, the wheels are exposed and therefore can contribute up to 40% of the vehicle's total drag (4) . The aerodynamic performance of front wings in isolation has been studied extensively in recent years (5)(6)(7)(8)(9)(10) , and several other reports on isolated.wheels have also increased knowledge about wheel performance when free of wing interference (11)(12)(13)(14)(15) . Intuitively, the close proximity of the front wheels to the front wing would be expected to have a strong influence on the overall system performance, yet the physics associated with the interaction of these two components remains poorly understood (1) .…”

Neural networks assisted computational aero-acoustic analysis of an isolated tire

“…For this study, automatic meshing algorithm is used to generate the mesh. 31,34 The tetrahedral elements are used in meshing, growing from the tire geometry with the help of refinement zones. 35 The tetrahedral elements growth rate in the adjacent refinement zones is selected 1.2 (20%) to minimize the computational error.…”