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A methodology for an efficient failure prediction of automotive steel wheels during fatigue experimental tests is proposed. The strategy joins the CDTire simulative package effectiveness to a specific wheel finite element model in order to deeply monitor the stress distribution among the component to predict damage. The numerical model acts as a Software-in-the-loop and it is calibrated with experimental data. The developed tool, called VirtualWheel, can be applied for the optimisation of design reducing prototyping and experimental test costs in the development phase. In the first section, the failure criterion is selected. In the second one, the conversion of hardware test-rig into virtual model is described in detail by focusing on critical aspects of finite element modelling. In conclusion, failure prediction is compared with experimental test results.

Developing of innovative technologies and materials to meet the requirements of environmental legislation on vehicle emissions has paramount importance for researchers and industries. Therefore, improvement of engine efficiency and fuel saving of modern internal combustion engines (ICEs) is one of the key factors, together with the weight reduction. Thermoplastic composite materials might be one of the alternative materials to be employed to produce engine components to achieve these goals as their properties can be engineered to meet application requirements. Unidirectional carbon fiber reinforced PolyEtherImide (CF/PEI) thermoplastic composite is used to design engine connecting rod and wrist pin, applying commercial engine data and geometries. The current study is focused on some elements of the crank mechanism as the weight reduction of these elements affects not only the curb weight of the engine but the overall structure.

In this paper a semi-analytical (SA) algorithm developed for the solution of the contact problem between two mating spur gears is presented and its application to the study of engagement dynamics is shown. Firstly, a quasi-static two-dimensional (2-D) approach is implemented to solve the contact taking into account several flexibility contributions related to the mating gears. In detail, a modified Hertzian model for the investigation of the real contact area considering the variable curvature of the profiles is developed. A comparison between this model and the classical Hertzian model is shown: the limitations of the classical method, for instance the possibility of analyzing bodies with varying curvatures and the peaks of pressure due to corner contact are therefore overcome. Furthermore, all the different tooth and gear deformations due to the meshing interaction are shown. This allows the computation of the Static Transmission Error (STE), main source of vibration and noise.

In racing design, important and urgent problems have to be solved: on one hand an high level of optimization of shapes and weights is needed for achieving high performance, on the other hand a quick development time is necessary to reduce the time between the new concept and the actual application on racing car as many redesigns are carried out during racing season. In the present paper, a quick design strategy for the brake disc mounting bell is proposed in order to reduce the development time and to reach an high accuracy for improving car performance. The brake disc mounting bell is a poorly studied component, but it has important side effects on the handling and the efficiency of a racing car. The proposed design strategy is developed by means of thermal and static finite element analysis (FEA).

In rally competition cars, the safety of vehicle occupants is currently projected without precise regulations. In order to reduce design time and control testing costs, finite element approaches and numerical comparisons between different solutions are used to reduce costs and improve performance. Within, a methodology and case study for attainting this goal are proposed. Using a numerical model of a rally car, different materials are compared and design indications are noted. A numerical non-linear model of half of a competition car roll-cage and its related door parts is built, in order to simulate the dynamics of lateral impact with a tree. Several numerical tests are conducted with the different absorbent materials and with different design solutions. Based on the deformation energy and acceleration of the roll-cage structure, an evaluation criterion is proposed.

Thermo-structural behavior of two cast iron commercial exhaust manifolds is investigated through transient nonlinear finite element analysis (FEA). Two different FE models are presented. The first FE model considers interaction between exhaust manifold, gasket and cylinder head. It also considers fasteners initial pretension and geometric constraint conditions. The second FE model only considers the exhaust manifold. Thermal exchange interfaces are evaluated and thermal analyses are conducted to evaluate thermal distribution and to obtain thermal inputs for structural analysis. FE models are solved for stress-strain estimation. Numerical results are validated with experimental data.