Research on the Automobile Aerodynamic Field at the Politecnico di Torino in the Second Half of the Twentieth Century

With this paper the author first of all wants to honor the memory of Professor Alberto Morelli with whom he had the privilege of working for many years at the Politecnico di Torino. Morelli radically changed the way of designing car body shapes, while bringing the aspect of reducing the aerodynamic resistance of a vehicle to the attention of car designers. Morelli’s research activity began in the early 1950s and, between the 1950s and 1960s, he designed and built a number of car prototypes, whose coefficient of aerodynamic resistance was substantially reduced compared to that of the cars of that time, sometimes resorting to revolutionary architectures such as a “diamond” arrangement of the wheels. A fundamental step of Morelli's research in the field of vehicle aerodynamics was the Pininfarina full-scale wind tunnel project, which was set up between the end of the 1960s and the beginning of the 1970s, and was inaugurated in 1972: fifty years have therefore passed since that occasion. An impressive result, obtained in the second half of the 1970s, was the maquette of the Pininfarina-CNR car, which had front air intakes, internal flows as well as other external details, such as rear-view mirrors: in this case, the Cx value was 0.20. His activity continued with significant results in the field of car aerodynamics, in particular concerning the interaction between the wakes of the car and of the wheels.