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High-field REBCO magnets contain several coils with many turns. {For these magnets,} electro-thermal quench is an issue that magnet designers need to take into account. Thus, there is a need for fast and accurate software to numerically model the overall performance of full-scale magnets. High temperature superconductors can be modeled using different techniques for electro-magnetic (such as $H$-formulation and $A-V$ formulation) and thermal (finite element method) analysis. However, it takes a lot of time to model the electro-magnetic and electro-thermal behavior of superconductors simultaneously in a commercial software, especially for non-insulated or metal-insulated coils. We have developed a novel software programmed in C++, which performs coupled electro-magnetic and electro-thermal analysis using variational methods based on Minimum Electro-Magnetic Entropy Production (MEMEP) and Finite Difference, respectively. The developed software is applied to axi-symmetric fullscale magnets of more than 30 T field strength for transient design (thermal quench reliability), taking screening currents into account. We show that the magnets incorporating non-insulated coils {are more reiable against quench} than the metal insulated coils. Also, {realistic} cooling conditions at boundaries is essential for such simulations. The model developed can be used for a quick and complete electro-magnetic and electro-thermal analysis of superconducting high field magnets., Comment: Improved figures. Corrected text

High temperature REBCO superconducting tapes are very promising for high-field magnets. Under high magnetic fields there are high electro-mechanical forces, and thus concern for mechanical damage. Due to large screening currents and composite structure of the tape, the mechanical design of these magnets is not straightforward. In addition, many contemporary designs use insulated winding. In this work we develop a novel two-dimensional axisymmetric finite element tool programmed in MATLAB that assumes the displacement field within linear elastic range. The stack of pancakes and a large number of REBCO tape turns are approximated as an an-isotropic bulk hollow cylinder. Our results agree with uni-axial stress experiments in literature, validating the bulk approximation. Here, we study the following configuration. The current is first ramp up to below the critical current and we calculate the screening currents and the forces that they cause using the MEMEP model. As a case study, 32 T REBCO superconductor magnet, is taken and simulated numerically. We have done complete mechanical analysis of the magnet by including the axial and shear mechanical quantities for each pancake unlike previous work where only radial and circumferential quantities are focused. Effect on mechanical quantities without screening current is also calculated and compared. It is shown that including screening current induced field strongly affect the mechanical quantities, specially the shear stress. The latter might be the critical quantity for certain magnet configurations. Additionally, in order to overcome high stresses, a stiff over banding of different material is considered and numerically modelled which significantly reduces the mechanical stresses. The FE based model developed is efficient to calculate the mechanical behaviour of any general superconductor magnet and its devices.

REBCO high-temperature superconductors are promising for fully superconducting high-field magnets, including ultra-high field magnets. Non-insulated (NI) and metal-insulated (MI) windings are a good solution for protection against electro-thermal quench. Design and optimization requires numerical modelling of REBCO inserts for high-field magnets. Here, we detail a fast and accurate two-dimensional (2D) cross-sectional model for the electromagnetic response of NI and MI coils, which is based on the Minimum Electro Magnetic Entropy Production (MEMEP). Benchmarking with an $A-V$ formulation method on a double pancake coil shows good agreement. We also analyse a fully superconducting 32 T magnet with a REBCO insert and a low-temperature superconducing (LTS) outsert. In particular, we analyze the current density, the screening curren induced field (SCIF), and the AC loss. We have shown that metal-insulated coils enable transfer of angular current in the radial direction, and hence magnet protection, while keeping the same screening currents and AC loss of isolated coils, even at relatively high ramp rates of 1 A/s. Surprisingly, soldered coils with low resistance between turns present relatively low AC loss for over-current configuration, which might enable higher generated magnetic fields. The numerical method presented here can be applied to optimize high-field magnets regarding SCIF in MI or NI magnets. It also serves as the basis for future electro-thermal modelling and multi-physics modeling that also includes mechanical properties.

The proliferation of technologies, such as extended reality (XR), has increased the demand for high-quality three-dimensional (3D) graphical representations. Industrial 3D applications encompass computer-aided design (CAD), finite element analysis (FEA), scanning, and robotics. However, current methods employed for industrial 3D representations suffer from high implementation costs and reliance on manual human input for accurate 3D modeling. To address these challenges, neural radiance fields (NeRFs) have emerged as a promising approach for learning 3D scene representations based on provided training 2D images. Despite a growing interest in NeRFs, their potential applications in various industrial subdomains are still unexplored. In this paper, we deliver a comprehensive examination of NeRF industrial applications while also providing direction for future research endeavors. We also present a series of proof-of-concept experiments that demonstrate the potential of NeRFs in the industrial domain. These experiments include NeRF-based video compression techniques and using NeRFs for 3D motion estimation in the context of collision avoidance. In the video compression experiment, our results show compression savings up to 48\% and 74\% for resolutions of 1920x1080 and 300x168, respectively. The motion estimation experiment used a 3D animation of a robotic arm to train Dynamic-NeRF (D-NeRF) and achieved an average peak signal-to-noise ratio (PSNR) of disparity map with the value of 23 dB and an structural similarity index measure (SSIM) 0.97.

The design of superconducting applications containing windings of superconducting wires or tapes requires electro-thermal quench modelling. In this article, we present a reliable numerical method based on a variational principle and we benchmark it to a conventional finite difference method that we implemented in C++. As benchmark problem, we consider a racetrack coil made of REBCO superconducting tape under short circuit, approximated as a DC voltage that appears at the initial time. Results show that both models agree with each other and analytical limits. Since both models take screening currents into account, they are promising for the design of magnets (especially fast-ramp magnets) and power applications, such as the stator windings of superconducting motors or generators., Comment: 17 pages, 6 figures