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This paper provides a review on state-of-art modern cooling systems employed for thermal cooling of electric motors for vehicle applications. In recent years, the pursue of a more sustainable and ecofriendly mobility has pushed the research towards the development of electric vehicle powertrain systems. Besides the evident advantages of the adoption of electric traction systems in terms of pollution and efficiency, the need of an effective cooling system for the electric machine components gained more and more importance in order to maintain high efficiency and ensure high durability. In fact, it is known that high temperatures can be harmful for the electric motor: besides the evident damages for mechanical parts, the influence on the permanent magnet properties is not negligible [1] [2]. In this fast-evolving environment, different solutions for the thermal problem have been researched and adopted, each one with its own pros and cons.

In this paper the lightweight design and construction of road vehicle aluminum wheels is dealt with, referring particularly to safety. Dedicated experimental tests aimed at assessing the fatigue life behavior of aluminum alloy A356 - T6 have been performed. Cylindrical specimens have been extracted from three different locations in the wheel. Fully reversed strain-controlled and load-controlled fatigue tests have been performed and the stress/strain-life curves on the three areas of the wheel have been computed and compared. The constant amplitude rotary bending fatigue test of the wheel has been simulated by means of Finite Element method. The FE model has been validated by measuring the strain at several points of the wheel during the actual test. From the FE model, the stress tensor time history on the whole wheel over a loading cycle has been extracted.

The aim of the paper is to provide simple and accurate analytical formulae describing the straight motion of a road vehicle. Such formulae can be used to compute either the steering torque or the additional rolling resistance induced by vehicle side-slip angle. The paper introduces a revised formulation of the Handling Diagram Theory to take into account tire ply-steer, conicity and road banking. Pacejka’s Handling Diagram Theory is based on a relatively simple fully non-linear single track model. We will refer to the linear part of the Handling Diagram, since straight motion will be considered only. Both the elastokinematics of suspension system and tire characteristics are taken into account. The validation of the analytical expressions has been performed both theoretically and after a subjective-objective test campaign. By means of the new and unreferenced analytical formulae, practical hints are given to set to zero the steering torque during straight running.