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Summary: Concrete‐encased columns reinforced with one built‐up steel core are widely used as mega columns in high‐rise buildings. Due to the enormous size of the steel core, multiple steel segments have to be welded and spliced on‐site, which might inflict detrimental impacts on the integrity and ductility of the columns. To solve this practical issue, one method using multiple steel sections to replace one gigantic built‐up section is proposed. However, whether those columns reinforced with individual steel sections could have the same capacity as the ones reinforced with one steel core and whether the current design method relying on strain compatibility is still applicable to design such columns remain unknown. In this study, one column specimen reinforced with multiple steel sections is tested and the test results are utilized to calibrate finite element models. Afterward, finite element (FE) analysis is performed on concrete‐encased columns reinforced with multiple steel sections to numerically examine the load capacity of those columns. Based on the numerical analysis, a design method based on modified strain distribution is proposed. Numerical results indicate that concrete‐encased columns reinforced with multiple steel sections exhibit similar performance compared with the one reinforced with one steel core, showing great potential to be applied as mega columns in high‐rise buildings. [ABSTRACT FROM AUTHOR]

In this paper, a new axial-type magnetic gear with an auxiliary flux-enhancing structure (AFS-AMG) is proposed. Compared to conventional AMGs, it has a higher torque density and higher permanent magnet (PM) utilization factor. Firstly, the design rules and operating principles of the proposed AFS-AMG are elaborated. Then, the mapping relation between the radial-type magnetic gears (RMGs) and AMGs are elucidated. Compared to its counterparts in RMGs, the AFS-AMG achieves a small size. Then, the geometrical parameters of the AFS-AMG are optimized to obtain better electromagnetic performance, where the torque density per volume and per PM volume is adopted as the evaluation standard. Finally, three different AMG topologies are constructed in finite element analysis (FEA) software for comparison. It is proven that the AFS-AMG has the largest torque density per volume and per PM volume. [ABSTRACT FROM AUTHOR]

This paper proposes an analytical model of the double-stator spoke-type permanent magnet vernier machine (DSSTVM) using the subdomain method (SDM), which can be used to calculate the magnetic field distribution and corresponding electromagnetic parameters of the DSSTVM. The whole field domain is divided into several subdomains according to the magnetic characteristics of each region, within which Laplace's and Poisson's equations are solved accordingly in terms of magnetic vector potential (MVP). Then, the corresponding magnetic flux density distribution, back electromotive force (EMF), and electromagnetic torque of the DSSTVM can be obtained. Ultimately, finite element analysis (FEA) is adopted to validate the proposed analytical model's effectiveness for quickly predicting the no-load and on-load performances of the DSSTVM. [ABSTRACT FROM AUTHOR]

• Crystal plasticity finite element model exhibits higher accuracy in evaluation of surface roughness and thickness distribution of cups fabricated by micro deep drawing. • The magnitude of surface roughness S z is almost linearly dependent on the average grain size of austenitic stainless steel foils. • The brass components are beneficial to the formation of drawn cups with uniform thickness distribution and the absence of severe defects. The present work involves the numerical simulation and experimental study on the surface roughness evolution and heterogeneous plastic deformation (strain localization and concomitant surface morphology evolution) in grain scale of micro deep drawn parts of austenitic stainless steel (ASS) 304 foils. A three-dimensional modeling framework was used to simulate the micro deep drawing (MDD) process. The simulation involved the development of a Voronoi-based polycrystalline geometry model (VPGM), a multi-stress-strain response model, and a crystal plasticity finite element methods (CPFEM) model. The results indicate that CPFEM model exhibits higher accuracy in the localized stress and strain, thickness distribution fluctuation and surface roughness evolution of the fabricated parts compared to multi-stress-strain response model. Therefore, the plastic deformation heterogeneity in MDD is in-depth discussed based on CPFEM model. The results show that the coarse-grained foils correspond to the intense strain localization, which is the main cause of surface roughening. Considering the average grain size is close to the thickness of ASS foils, mounding features on the rough surface may readily develop further into potentially fractured sites during deformation. On the other hand, crystal orientation influence plastic deformation by affecting the slip behavior of materials. The effect of crystal orientations including {011} 〈211〉 (Brass), {011} 〈100〉 (Goss), and {112} 〈110〉 components on deformation is discussed. The results indicate a strong correlation between the magnitude of the Schmid's factor and the ease of deformation. Additionally, variations in Schmid's factor across different directions result in differences in deformation accumulation, which affects the thickness distribution along the radial direction and the distribution of earrings and wrinkles along the circumferential direction of the fabricated micro parts. [ABSTRACT FROM AUTHOR]