2 min read •
27 de março de 2016
Sport-Prototype - A Childhood Dream (Part 3)
by
Antonio Eiras
In drawing 6 we can observe that there are only two very simple flux deviators, on the rear diffuser. Here is another Technical Regulation’s limit that, also, imposes that these flux deviators must be placed in a parallel and symmetric position, between them and the longitudinal axle of the car.
Placed over the trailing edge of the rear diffuser, the exhaust of the gas escape from the engine will boost the air that flows on this aerodynamic device, increasing its velocity and the efficiency of the diffuser.
At each side of the rear diffuser, and behind the rear wheels, there is a device, imposed by ACO Technical Regulations, that not only avoids any backwards projection of detritus, and of the turbulent air flow from the wheels, over any persecuting car, but, also, by the induced acceleration on the air that flows out from the same rear diffuser, and that is forced to do a 270 degrees angle, in the horizontal plane, improves this device’s efficiency.
On drawing 5 we can see, on the lateral face of the side pod, the out flow of warm air, in red arrows, that cooled the radiators, from small vertical fences. The warm air that flows out from the air exchangers is, in turn, drained from small louvers opened on the beginning of the upper surface of the engine cover.
On this area we find two air intakes in each side pod: the inner one will feed the same side turbo, and the upper, a periscope one, will canalize the cooling air flow to the rear brakes (drawing 2).
In the same drawing we can follow the engine cover curvature, backwards and downwards, progressively, to reach the trailing edge with a Gurney flap, and also, how the air flow, that will cross the rear wing, is aspirated, in a downwash, by the engine, gearbox and rear wheels bodywork cover.
This air flow will form, with the rear wing, a higher effective angle of attack, than the one that would result from the interaction between the rear wing with a non conditioned free air flow.
This higher angle of attack will, naturally, increase the downforce generated by the rear wing, with a small extra drag.
Together with this highly refined aerodynamic package, the R10 has a very effective chassis, a powerful and economic engine, and a reliable gearbox. And so, with this superb Sport-Prototype car, Audi won the 24 Hours of Le Mans, and placed very high the level of efficacy of these vehicles.