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The implementation of increasingly stricter regulations on CO2 emissions by the European Community is pushing the automotive industry towards a radical change. In a rush to electrify their model ranges, global carmakers are investing heavily on developing new electrified powertrains. Within this context, this work focuses on the analysis of electric axles drives (eAxles) for a BEV (battery electric vehicle) sport car, with the aim to develop an analytical tool useful to perform predictive analysis in the concept design phase. Through a parametric definition of the procedure, the tool is able to “adapt” to any drivetrain layout analysed. The tool actually allows to enter more than 100 input values including lubrication conditions (oil viscosity and operating temperature), gears (number, macrogeometry, mesh), bearings (number, type, geometry, mounting layout, angle mesh), shafts, oil seals, external layout and external fluid conditions.

An engine head of a common rail direct injection engine with three in line cylinders for Light Transportation Vehicle (LTV) applications has been analyzed and optimized by means of uncoupled CFD and FEM simulations in order to assess the strength of the components. This paper deals with a structural stress analysis of the cylinder head considering the thermal loads computed through an CFD simulation and a detailed FV heat-transfer analysis. The FE model of the cylinder head includes the contact interaction between the main parts of the cylinder head assembly and it is subjected to the gas pressure, thermal loads and the effects of bolts tightening and valve springs. The results, in term of temperature field, are validated by comparing with those obtained by means of experimental analyses. Then a fatigue assessment of the cylinder head has been performed using a multi-axial fatigue criterion.

An engine head for microcar applications has been analysed and optimized by means of uncoupled CFD and FEM simulations in order to assess the strength of the component. This paper deals with a structural stress analysis of the cylinder head considering the thermal loads computed through an uncoupled CFD simulations of cylinder combustion and in cooling flow passages. The FE model includes the contact interaction between the main parts of the cylinder head assembly and it also considers the effects of bolts tightening and valve springs. Temperature dependent non-linear material properties are considered. The results, in term of temperature field, are validated by comparing with those obtained by means of experimental analyses; the engine has been instrumented with thermocouples on crank case and on cylinder head.

Riveting is a well established technology in the manufacturing of aeronautical structures as well as in the automotive industries. Despite its simplicity, the rivet presents a local stiffness that is not easy to properly model within a large finite element analysis. However, precision in the local stiffness evaluation is essential to perform any structural analysis when several rivet are applied in a joint structure. The result is that any rivet requires a local mesh refinement or, and this is the most common case, a drastic simplification of its structural modelling characteristics. In the present paper the structural behavior of a riveted lap joint connection was investigated experimentally and numerically using a new rivet finite element. The Rivet Element, based on a closed-form solution of a theoretical model of the rivet joint, is able to precisely evaluate, in FE analysis, both local and overall stiffness of riveted joints with a very low contribution of dofs.

The authors have developed an original spot weld finite element based on a theoretical solution condensed on the nodes that surround the spot weld region. The spot model was successfully used in the elastic case, which is useful for high cycle fatigue life predictions. An improved version accounted also for the progressive damaging due to fatigue evolution by means of appropriate stiffness reduction of the spot nugget. By this way, load redistribution under progressive damaging can be accounted. In this paper, the spot weld is studied when plastic deformations are experienced by the structure. This is the case of occasional overloads but also the more drastic case involving structure crashes. The groups of beams that connect the spot core to the metal sheets, already set up in the fatigue computation, are modified so that to account of irreversible deformations. Here again the developments are based on an analytical approach even if several simplifications reduce overall accuracy.

Riveting is a well established technology in the manufacturing of aeronautical structures as well as in the automotive industries. Despite its simplicity, the rivet presents a local stiffness that is not easy to properly model within a large finite element analysis. However, precision in the local stiffness evaluation is essential to perform any structural analysis when several rivet are applied in a joint structure. The result is that any rivet requires a local mesh refinement or, and this is the most common case, a drastic simplification of its structural modelling characteristics. In the present paper a new rivet element is introduced, able to precisely evaluate both local and overall stiffness of riveted joints; this finite element can be applied when dealing with 3D riveted shell structures. The modelling approach is similar to that, developed also by the author for spot welds.