This paper shows that the dynamic study of a railway vehicle in curve can be reduced tothe study of a bogie and two wheelsets in the quasi-static case. Every wheelset supportsthe load of the quarter of the vehicle. From this model, we can optimize the suspension todefine the mechanical build characteristics of vehicle.

Conventional methods (i.e. time, frequency and cepstrum) can routinely be used to revealfault-indicating information in the vibration signal. In recent years, wavelet analysis,which can lead to a clear identification of the nature of faults, is widely used todescribe rotating machine condition. The capability of this method in the detection of anyabnormality can be further improved when its low-order frequency moments are considered.This paper presents the use of the fast kurtogram in the early detection and conditionmonitoring of pitting fault. For this purpose, a dynamic model of a simple stage gearbox(with and without defects) is used. Then, the pinion’s vibration displacement is analyzedby using a fast kurtogram method. This method is suitable for such diagnosis and givesvaluable information about the presence and effects of the pitting tooth defect.

Measurement of heat fluxes and electrodes temperature in a proton exchange membrane fuel cell were performed using platinum wires and heat flux sensors. A temperature difference of 6 °C to 9 °C between the electrodes and the bipolar plates was observed for a cell operating at a current density of 1.5 A.cm-2. These measurements show a strong non-uniformity of the temperature profile through the membrane electrode assembly that future models should take into account. Simultaneous heat fluxes measurements have allowed to evaluate in situ the effective thermal conductivity of the porous layers. Values of the order of 0.3 W.m-1.K-1 were found.

In this paper, strain gradient theory is used in developing a mathematical model based on classical flexural Kirchhoff plate theory that can predict static response of rectangular micro-plates. The result of this new model is a sixth order differential equation. Order of differential terms in Galerkin weak form of the equation is reduced so that C2 hierarchical p-version finite elements with second order global smoothness can be used to solve the problem. With different boundary conditions, the computed deflection distribution of micro-plates is compared with those of the classical theory, in which length scale parameters are not present. A series of studies have revealed that when length scale parameters are considered, deflection of a rectangular plate decreases with increasing the length scale effect; in other words micro plates exhibit more rigidity than what is predicted by the classic model. Here, deflections are normalized with respect to results obtained from classical plate theory. Comparison of maximum deflection values obtained from the extended model for micro plates with those available from the classic plate model indicates that classical theory overestimates displacement values and the largest error is observed for square micro plates. The overestimation levels off for plates with aspect ratios greater than three.

The sheet metal forming by shearing is one of the most used processes in industries. The reliability of the obtained parts depends on geometrical parameters (shape of the tools, punch radius, clearances, velocity...) and materials properties (metal behavior, friction...). In this paper, two experimental parameters are investigated: the punch – die clearance and the punch velocity. A 0.65 mm thickness sheet of a non-oriented full-process Fe-(wt.3%)Si is used. The analyses are done through the load-stroke curve and the height repartition of different defects on the part edge. A numerical approach is proposed to simulate the shearing process and to handle the ductile fracture (which is performed using Abaqus/Explicit software). This work is based on a non-iterative explicit algorithm combined with a mesh adaptivity method (Arbitrary Lagrangian Eulerian formulation). The Gurson–Tvergaard–Needleman model is then used to describe the cut edge profile occurring during the process.

In this study, numerical models based on finite-element method are developed for severalapplications of fracture mechanics. The use of cracked specimens formed by differentmaterial properties has allowed us to analyse the effect of the crack position to theinterface and to have a well understanding of mismatch effect for the case of mixed modeof fracture. In other hand, we have noticed that it is very interesting to see the effectof the interface position and loading for the case of symmetrically cracked ring specimenunder compression loading.