ESCORPIO - AERODYNAMICS
Escorpio Evo2k17 is very similar to the previous version, but apart from the general shape, the major changes are the height from the ground, which is increased, and a smaller frontal area, decreased by 10%.
This allows the car to reach a Cx value of 0,109.
Official rules changed: rear wheel steering is no longer allowed!
This forced us to design and build a brand new vehicle, which has to be wider in the front, to allow the steering movement of the front wheels.
The first step is the drawing, and then the test of the shape in a sort of virtual wind tunnel, best knows as CFD (Computational Fluid Dynamics) provided by SolidWorks software.
Sooner or later, it had to happen: the first contact took place after we read a newspaper article, reporting about Fondtech company and the electric "formula" racing car they were developing.
A quick e-mail to introduce us: we are working on an electric car too, it's just a bit slower... then after the first visit into the factory with a scale model of Escorpio, Fondtech confirmed the availability of the wind tunnel for an entire day of testing!
Final checks before the start of the test, Escorpio is almost ready to "hit the air": small ropes are fixed on the body to observe the direction of the airflow in all the different areas of the prototype.
Escorpio seems to behave well during the test session in the wind tunnel, from which its excellent aerodynamics features are confirmed.
The wing spread used to draw the bodyshell were gradually modified, in order to achieve the best result in terms of resistance coefficient (Cx). To do this, a CFD software simulation (Computational Fluid Dynamics) was used to supply a series of data and useful information to improve the geometry of the vehicle. In order to prove these simulations, and to obtain quantitative results, it would be useful to test the vehicle in a wind tunnel.
The Cx of cars currently in circulation is between the good 0.26 of the Toyota Prius and the bad one 0.57 of Hummer.
Remarkable value of all respects was reached by the CNR prototype (in the photo), designed by Mr. Morelli (teacher) at the Turin Polytechnic in 1979 with Cx of 0.17.
The vehicle, however, was never put into production, perhaps due to its too "futuristic" shape.
From this view you can see properly the "waterdrop " shape of the bodyshell.
The aerodynamic penetration coefficient "Cx " obtained by this simulation turns out to be equal to 0.12: very good!
From our studies it emerged that the most interesting shape to choose was that of a "water drop", in fact it has a much lower Cx compared to other forms; it also suits to the geometry of our prototype.
Nogaro 2023: 5nd place in the battery electric prototypes category.