The role of the WW, touched on above, will now be discussed in a little more detail. In passing the lower section of the WW, the lower vortex generated by the barge board produces a pressure difference between the upper and lower sections of the WW, which generates the tip vortex from the WW and increases the intensity of the barge board lower vortex. The WW also play another important role. As Fig. 20 shows, the flows at 5.4. Downwash produced by SPLEF

The side-pod leading-edge flickups (SPLEF) are vertical plates with L-shaped YZ sections that are positioned on the exterior of the side pods (Fig. 21). The role of the SPLEF is to intensify the downwash to the HH by providing a blockage and producing circulation. The use of the SPLEF increases the downforce of the HH, but they also generate high levels of induced drag and pressure drag acting on them. However, it was possible to increase the lift-drag ratio through the application of treatments to the leading edges of the vertical plates and the optimization of their shape. 5.5. Ideal Flow Figure 22 shows the surface streamlines from the nose to the chassis. The figure shows that the use of chassis upper and lower aero parts has resulted in the FW upwash being rapidly directed towards the underfloor the ideal flow for a Formula One vehicle, as described in section 2.2. 1 Vane vortex Vane vortex 2 Vane vortex Vane vortex Upper vortex Upper vortex Fig. 21 SPLEF

Lower vortex 1 2 Fig. 19 ONF vortices Fig. 22 Surface streamlines 6. Bodywork WW WW HH HH The bodywork refers to the areas around the side pods (SP) and the cowl. 1 6.1. Effect of SP Undercut Fig. 20 Channel flow From 2000, most teams began using a curved shape called an undercut for the lower sections of the anterior halves of the SP [Fig. 23(b)]. 157

Aerodynamics Analysis of Formula One Vehicles The SP undercuts can be indicated as having three main effects. The first of these is an underfloor seal effect. The circle in Figure 24(b) shows a hypothetical side wall connecting the side edges of the floor and the ground vertically. Without such a side wall, the flows from the leading edges of the SP flow out from under the floor and flow back under the floor and towards the diffuser, but part of the flows also flow out towards the rear tires [Fig. 24(a)]. By contrast, with side walls in place, the underfloor flows are sealed in and flow in straight lines to the diffuser. This accelerates the underfloor flows, boosting suction and increasing downforce [Fig. 24(b)]. However, because the flows towards the rear tires are also blocked, the suction at the leading edges of the SP tends to become weak. In other words, if only the middle and the rear section of the floor was sealed, the maximum benefit of the seal effect could be obtained.