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Electric Vehicle Battery Thermal Management Using Hybrid Heat Pipe-Cold Plate Cooling System
No full textThis study investigates the thermal performance of a hybrid battery thermal management system (BTMS) designed for electric vehicles, which integrates both a heat pipe and a cold plate for enhanced heat dissipation. The experimental results demonstrate that the system is capable of effectively dissipating heat input powers up to 40 W while maintaining the battery module temperature below the critical safety threshold of 60 °C. The BTMS leverages the high thermal conductivity and passive operation of heat pipes, coupled with the efficient convective cooling provided by the water-cooled cold plate. Comprehensive thermal characterization is performed through both computational fluid dynamics (CFD) simulations and infrared thermography, allowing for precise analysis of heat transfer phenomena within the system. The simulation results closely match the experimental infrared measurements, confirming the reliability and predictive capability of the numerical model. These findings underscore the system’s potential for ensuring temperature uniformity and thermal safety in next-generation electric vehicle batteries. Moreover, the integrated hybrid cooling solution provides a promising pathway toward scalable and compact BTMS architectures, meeting the evolving requirements for performance, reliability, and energy efficiency in electric mobility applications
Development and application of soft X-ray spectroscopy and cathodoluminescence to minerals
No full textThe addition of hyperspectral soft x-ray emission spectrometers (SXES) and cathodoluminescence (CL) spectrometry to electron microprobes gives access to spectroscopies that provide sample information not available from wavelength-dispersive (WDS) or energy-dispersive X-ray spectrometers (EDS). We have developed software and hardware which enables collection of the backscatter electron signal, WDS, EDS, SXES and CL spectral data simultaneously. This unique strategy allows our instrumentation to avoid pixel misalignment and minimises electron beam induced damage artefacts associated with multiple pass mapping. Originally this approach was developed for a JEOL 8530F-CL and most recently has been implemented on a JEOL iHP200F-CL. We have utilised this technology on a range of material and geological problems. Here we show an example of grain orientation information that can be obtained from SXES spectra collected during mapping naturally occurring graphite from a Tanzanian deposit. In addition, a ureilite meteoritic sample, NWA7983, was studied to better understand the formation and presence of lonsdaleite and diamond
ICRF near-field effects sensitivity to magnetic tilt-angle
No full textThis paper complements the study reported in
G. Urbanczyk et al 2025 Nucl. Fusion 65 046018 by investigating how near-field effects from Ion Cyclotron Range of Frequency (ICRF) antennas depend on the magnetic geometry, particularly focusing on the sensitivity of rectified sheath potentials and associated impurity production to variations in magnetic field tilt-angle. Simulations were conducted using Petra-M, employing a flat model of the ASDEX Upgrade (AUG) three-strap antenna, and COMSOL, utilizing a curved model of the WEST antenna. Results demonstrate indications of sensitivity of the rectified sheath potentials and impurity sputtering to the alignment of Faraday screen bars with the magnetic field lines, emphasizing the necessity for careful consideration of geometric alignment in antenna design for fusion devices. This trend is consistent with experimental data measured with various diagnostics
The effect of high-power transient events on tungsten and tungsten coatings used for radio frequency launcher applications
No full textHigh-temperature plasma-facing material coatings used for radio frequency (RF) launchers need to be robust enough to survive RF breakdown arcing or other transient events from the plasma (e.g., an edge localized mode) without causing a catastrophic failure of the coating. High-power transient effects are being explored by using an RF-induced vacuum arc to determine the robustness of tungsten coatings made by a variety of manufacturing methods. A 1/4-wavelength resonant section of vacuum transmission line terminated with an open circuit electrode structure with a well-defined electric field (30-60 kV/mm) produces repeatable arcing conditions. The initial focus is on tungsten as a plasma-facing material, including sintered tungsten, tungsten coatings on steel produced via physical vapor deposition (PVD), and functionally graded tungsten/steel coatings deposited by low-pressure plasma-spraying (LPPS). Thin PVD coatings (1-2 microns) fail catastrophically from an arc and result in severe delamination of the coating. The arc-induced damage of thicker coatings, such as those made via LPPS, tend to be restricted to the top few microns of the surface. Arcing often initiates on sharp surface microstructures and causes localized melting of tungsten at the surface of all the materials studied and results in resolidified melt pools with surface cracks. The resolidified surface results in a reduction in overall deuterium retention when exposed to typical RF plasma sheath conditions
Multidimensional modulational instability and associated multi-rogue waves in anisotropic magnetized superthermal plasmas
No full textIn this study, we examine three-dimensional (3D) modulated ion-acoustic waves (IAWs) and associated multi-rogue waves in a magnetoplasma consisting of kappa-distributed electrons and hot, anisotropic positive ions. By employing a reductive perturbation technique (the derivative expansion method), the fundamental fluid equations are reduced to the three-dimensional nonlinear Schrödinger equation (3D-NLSE) to investigate the 3D modulational instability (3D-MI) and associated modulated IAWs. For the plasma parameters of interest, such as the anisotropic parallel ion pressure, magnetic field (ion gyrofrequency), and the spectral index of the kappa distribution, the stable and unstable regions of modulated envelope structures are precisely identified. The criteria for the 3D-MI based on the 3D-NLSE are determined and numerically examined. Furthermore, the analytical and numerical solutions for first-order and second-order ion-acoustic rogue waves (IARWs) are investigated. The effects of relevant plasma parameters on the IARW profile are also examined. The implications of our findings for specific environments, such as Earth’s magnetosheath and magnetosphere, are also discussed
Design and Manufacturing of Axial Flux Permanent Magnet Machines for Electric Vehicle Applications
No full textThis paper presents the design and prototyping of an open-slot, 18-slot, 12-pole, axial-flux, permanent-magnet (AFPM) machine that meets the typical requirements of electric vehicles. A multiphysics design approach was used to consider mechanical and thermal constraints during the design stage. The electromagnetic design is based on a combination of 2D and 3D finite element analysis (FEA) approaches. Segmenting the rotor and optimizing the rotor disc material reduce rotor losses. This provides a balanced compromise between eddy current losses and manufacturing costs. The designed machine was manufactured and tested on a test bench under both no-load and load conditions. Experimental results, such as back electromotive force (Back EMF), torque as a function of current, magnet temperature, and torque and power versus speed curves, are compared with simulation results. The impact of the manufacturing process on performance, especially iron losses, is investigated. For this purpose, the iron losses are assessed using the stator yoke of the axial flux machine in both torus configuration test and an Epstein frame. These specific iron losses are then used to evaluate iron losses via 3D FEA. Several configurations are tested to evaluate different no-load losses, such as mechanical losses, magnet losses, rotor holder losses, and stator iron losses, as well as AC losses due to the proximity effect caused by the external magnetic field generated by the rotation of the magnets, in order to compare the calculated iron losses obtained by 3D FEA with the measured ones. Rotor losses in the magnet and rotor holder are evaluated by measuring the rotor temperature using an infrared sensor
Nanomineralogy of planetary materials
No full textThe scientific significance and scarcity of extraterrestrial rock and mineral samples means that techniques for nanoscale analysis are essential tools for planetary scientists. This review describes some applications of key methods for identifying minerals in meteorites and samples that have been collected and returned by space missions, and for characterising their crystal structure, microstructure, and chemical and isotopic compositions. The techniques covered are electron backscatter diffraction, transmission Kikuchi diffraction, scanning transmission electron microscopy, and atom probe tomography. In the near future, these tools may provide answers to very important questions including whether there is sufficient water on the Moon to support lunar habitats, and did life evolve on Mars
Getting your EBSD data right, combing optical microscopy and optical simulations from EBSD orientation data in MTEX
No full textIn this study we demonstrate how one can use the optical Tensor tool in free open-source toolbox MTEX add on to Matlab ® to confirm that EBSD orientations are correctly applied with respect to the desired representation of the data, both in plotting convention and sample reference orientation. We exemplify this with simulated optical and axial interference figures of quartz and calcite, respectively, but this is possible with any transparent minerals, where the optical properties are well defined. In addition, the simulations could also be applied to fit optical properties with EBSD data in cases where the optical properties are not known or to develop and test optical orientation methods as faster and cheaper techniques than EBSD. In the present case the correct alignment of Euler and sample reference frames is essential to confirm the relations between lattice preferred orientation and large scale left-lateral move on a regional shear zone
A new approach for material classification based on quantitative analysis
No full textAccurate identification and classification of a material based on energy dispersive spectrometry (EDS) has always been a challenge, down to the variability between systems, acquisition conditions, spectrum processing methods and accuracy in quantitative analysis results. Traditional methods rely on template spectra from known chemical compositions to match against an unknown spectrum. The spectrum matching algorithm assumes that template spectra are acquired with the same system and under the same conditions, which poses difficulties and in some cases is impossible. In this paper, a different approach is proposed based on quantitative analysis results as the basis for matching. Quantification-based matching removes the ambiguity introduced by different systems and acquisition conditions. Databases can be created based on the nominal composition of compounds without acquiring a spectrum from known samples. This paper explains the details of the matching algorithm and presents three examples to demonstrate the performance
Full-wave simulation of ion cyclotron range of frequency heating in a mirror device
No full textWe are adapting the all-orders spectral algorithm (AORSA) [Jaeger Phys. Plasmas 8 (2001)] from tokamak geometry to axisymmetric magnetic mirror geometry. We will use the modified AORSA to study ion cyclotron range of frequency (ICRF) heating in the Wisconsin HTS Axisymmetric Mirror (WHAM) magnetic mirror device [D. Endrizzi J. Plasma Phys. 5 (2023)]. ICRF power will be used in WHAM to accelerate high-energy neutral beam injected deuterium ions with ion cyclotron absorption at the second to fourth harmonics of deuterium. At these harmonics, for the spatial scales present in WHAM, full-wave simulations most accurately capture wave propagation, including transmission, reflection, and absorption at the cyclotron layer. The antenna is modeled as a single strap with
m = 0 excitation, where
m is the azimuthal mode number. We present some preliminary results for wave coupling and heating