This paper mainly proposes a general model of eccentric squirrel-cage induction motor (SCIM), which includes the stator and rotor slotting effect as well as their individual tooth reluctance effect. Considering open slots on the stator and rotor, their rather exact shape is included in the machine's air gap function. Then, the resulting air gap function is used for evaluating various inductances of SCIM by the winding function approach (WFA). A simple general technique is used for adding eccentricity effect, including static, dynamic, and mixed eccentricities, on the air gap function and, therefore, on the inductances. Using a novel technique, saturable reluctance of each tooth of the stator and rotor is evaluated in every simulation step. Then, these reluctances are added to the model by equivalent increase of the air gap in front of the teeth; this reflects the teeth saturable reluctance effect on the inductances of the SCIM. In effect, dynamic simulation of SCIM with all aforementioned effects using WFA becomes possible. Simulation results compared to corresponding experimental results show accuracy and exactness of the proposed model.

In this work we use density functional theory (DFT) calculations to benchmark empirical potentials for the interaction between nickel and sp 2 bonded carbon nanoparticles. These potentials are then used in order to investigate how Ni decorated or coated carbon nanotubes (CNT) affect the mechanical properties of Al/CNT composites. In particular we look at the pull-out behaviour of pristine as well as Ni-decorated and Ni-coated CNT from an Al matrix. Our result shows that Ni coating may produce an extended interface (interphase) where a significant amount of energy is dissipated during CNT pull-out, leading to a high pull-out force. We also demonstrate that surface decorated CNT may act as efficient nano-crystallization agents and thus provide a novel strengthening mechanism not previously discussed in the literature. We discuss our results in view of promising approaches for engineering CNT-metal interfaces such as to achieve high strength metal-CNT composites. arXiv:1907.05086v1 [cond-mat.mtrl-sci]

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Multiscale simulation study results of multilayer structures consisting of graphene sheets with embedded Pt nanoparticles is reported. Density functional theory is used to understand the energetics of Pt–graphene interfaces and provide reference data for the parameterization of a Pt–graphene interaction potential. Molecular dynamics simulations then provide the conformation and energetics of graphene sheets with embedded Pt nanoparticles of varying density, form, and size. These results are interpreted using a continuum mechanical model of sheet deformation, and serve to parameterize a meso‐scale Monte Carlo model to investigate the question under which conditions the free volume around the Pt nanoparticles forms a percolating cluster, such that the structures can be used in catalytic applications. This article is concluded with a discussion of potential applications of such multilayer structures.

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