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The magnetic pressure generated in the stator of electric machines can be a significant source of noise and vibration. The vibration behavior of the stator and such mechanical structures primarily depends on their geometry. Although the stator is often considered a simple structure, its teeth are not included in this assumption. In this paper, we endeavor to evaluate the impact of stator geometrical variability on the vibration behavior of electric machines. Our sensitivity study reveals that natural frequencies and frequency response functions are highly sensitive to geometrical variability. To account for this, we conducted a variability propagation study using a stochastic finite element model. Our findings show negligible variability on the natural frequencies but a high variability on the frequency response functions, even with low input variability. As anticipated, our study highlights the critical role of accounting for geometrical variability to enhance the accuracy of finite element models and strengthen their predictive power. However, the main contribution of this work is that the vibration behavior of the stator is not coupled, implying that the impact on natural frequencies does not necessarily reflect the same effect on the frequency response function. [ABSTRACT FROM AUTHOR]

Due to the complex microstructure of textile composites, the modeling of physical properties is challenging. The mechanical properties of textiles depend on different geometrical parameters such as the yarn's geometrical properties, undulation, geometrical cross-section, gap between two adjacent yarns, and other parameters. In this paper, a geometrical modeling of 2D and 3D woven composites is presented. The novelty of this paper is related to a more realistic modeling of yarn's cross-section. The presented modeling technique takes into account that yarns constituting 2D or 3D woven composite do not have the same cross-section shape and undulated part as usually considered with an ideal unit cell modeling. The proposed technique leads to calculate the fiber volume fraction of yarns, then the fiber volume fraction of the unit cell of the studied composite. It was applied to different kinds of woven composites where the modeled unit cell converged to a more realistic shape. [ABSTRACT FROM AUTHOR]