Analysis of the rear impact-absorption structure of a racing car

The work in which this thesis consists of has been made during an internship of six months in Ferrari Spa, in particular inside the Gestione Sportiva Sector. This is the Office which faces all the tasks involved in the Formula One competition: these go from designing all the components of the cars, testing them and racing in the championship. The Department which deals with the design of all the composite parts of the Formula One cars is called Autotelaio; these components are mainly wings, floor, diffuser, car body, chassis, suspension arms and gearbox. The last part is the one involved in this work, since the thesis is focused on the design of the so-called Pylon. The Pylon is mainly an energy-absorption structure, which has the function of protecting the gearbox from rear impacts and ensuring safety for the driver. In Chapter 1, a description of the component will be provided, considering its position in the car, its geometry and improvements from last year one. Furthermore, the evolution of its characteristics from the year of its introduction to nowadays will be shown. In Chapter 2, some significant studies on impact on composite structures will be mentioned, trying to explain the main modes of crushing, how they influence the energy-absorption capacity of the component and the influence of typical parameters considered by the designer in the shaping of a composite part. Moreover, an analytical way of calculating absorbed energy and mean load during crash will be mentioned. In Chapter 3, the regulations regarding the expected characteristics of the pylon will be quoted, underlining the tests (push-off and crash) that the component has to pass in order to receive the homologation from FIA Organization. In Chapter 4, an in-depth description of the designing and manufacturing of the pylon will be discussed, dividing it in three main phases: - shaping of geometry deriving from aerodynamic inputs, required to draw the manufacturing tools; - design of the finished component and the devices necessary to machine it and glue it on the gearbox; - construction of the laminate on 3D part and 2D plybook, making a consideration on materials used as matrix and fibre, the geometry and the sequence of plies; In Chapter 5, the push-off FEM analysis will be introduced, describing its distinctive characteristics, the settings of the FEM model (constraints, mesh, type of analysis, contact interfaces) and the interpretation of results. In Chapter 6, the testing of the pylon will be described, considering the setup of the facility and the instruments used for push-off and crash. The tests held are three in total, two using a dummy mounting which simulate the backward of the gearbox and the last with a realistic configuration pylon+gearbox. Results will be analysed, especially confronting them with FEM output, trying to establish a link between physical characteristics of the pylon, such as laminate configuration and geometry, and his structural behaviour. In Chapter 7, a conclusive overview on the improving of the component and some considerations about the costs involved in the manufacturing and testing will be made.