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The inductive assemblies with variable geometry have recently been proposed for potential electromagnetic (EM) energy harvesting utilization. Such inductors are capable of changing their initial geometry under the influence of some external force, collecting additional magnetic flux and producing increased induced voltage. In order to evaluate performance of such inductors, regarding increase of its...
In this paper, a Discontinuous Galerkin Time-Domain (DGTD) method is used to model full Ground Penetrating Radar (GPR) scenarios. The bi-static GPR is made of two identical Vivaldi antennas, which are accurately modeled in front of a sand box in order to detect and localize some buried objects. Our approach is validated by comparison with either synthetic data provided by CST-MWS or experimental data...
In this paper, analytic models are developed for segmented cylindrical electromagnetic actuators having a center hole. Analytic models developed are verified via extensive comparison to results obtained by finite-element analysis. Both analytical and finite-element results demonstrate that the segmentation of the stator results in dramatic improvements in actuator dynamic performance by reducing the...
This paper presents an analytical approach for calculating the magnetic field distribution excited by planar spiral circular coil and square coil for wireless power transfer (WPT) system. Based on Biot-Savart principle, the spatial magnetic flux density can be computed and the mutual inductance of the coils is calculated by numerical integrals with all possible variations of misalignments. The analytical...
Certain novel molecular diagnostics Point-of-Care applications require precise temperature control (±1–5 °C) over an extended time (15–60 minutes) for proper function. Microheating components in portable tests must meet strict criteria with respect to size and power consumption, both of which may be met with thermoelectric heating. Our proposed finite element model is intended to provide tools for...
This paper discusses the runner blade design of axial-flow hydraulic turbine type propeller using two different methods. The first method is considered with no-swirl flow at runner exit, while the second method with swirl flow at runner exit. The design results show that both methods produce the different stagger angle at each blade section of the runner blade. The numerical simulation was performed...
Accurate Power Distribution Network (PDN) design is crucial for Signal/Power Integrity (SI/PI) and Electromagnetic Interference (EMI) compliance. Achieving target power-ground (PG) noise levels for low power complex PDNs requires several design and analysis cycles. Although several classes of analysis tools, 2.5D and 3D, are commercially available, the presence of design tools are limited e.g. parametric...
Array antennas may be required to produce arbitrary polarizations for best match to far field sources or receivers at arbitrary angles. A common presumption is that this requires radiating elements with phase center coincidence (PCC). This paper shows the results of extensive numerical experiments with three dual-polarization radiator types, two with phase center coincidence and one without. The three...
Printed circuit boards (PCB) are subject to external electromagnetic interference. A validation tool to efficiently predict the worst-case induced voltages and currents is invaluable in the process of making PCB designs pass the immunity test for electromagnetic compliance. This paper proposes to use a 2.5-D hybrid finite-element-method (FEM) solver to characterize the radiated far field and use the...
Different geometry arrangement for elements in an array yields various electrical interactions between them. In a wide band and wide scan angle array, these interactions are quite complex. A smart array structure is proposed based on the planar octagonal ring antenna. Thanks to the flexibility of this array element, element sizes and the bonds between the elements in the array can be non-uniform,...
In this work, collapse of subsea pipelines subjected to external pressure which are dented by foreign objects is investigated through numerical method. The effect of diameter-to-thickness ratio D/t and ovalization caused by denting Δom on the collapse pressure is discussed. Of particular concern is the effect of indenter's shape on the collapse pressure. The collapse behavior between pipelines dented...
The high-intensity focused ultrasound (HIFU) has shown positive results in the treatment of prostate cancer and its possible application in neurodegenerative diseases. This paper describes the design of a HIFU applicator with a conical geometry, for modeling the software COMSOL® (COMSOL Inc., Burlington, MA) was used, which bases its operation on the finite element method (FEM). The equations that...
The transformation electromagnetics is applied to the modeling of electromagnetic scattering from periodic structures in conjunction with the finite element method with periodic boundary conditions. In a unit cell of periodic structure, a uniform mesh is used over a flat surface and the arbitrary periodic surface is modeled by a coordinate transformation. The major advantage of this approach is that...
In this article, we present the development of Java library implementing Discrete Exterior Calculus (DEC) constructs using the Processing IDE rendering environment to analyze WaveFront .obj objects. The library contains common DEC structures and operators found in other implementations and provides local iterators to explore the topological relations that DEC theory relies on, along with classes able...
In Shear Wave Elastography, quantitative tissue characterization for dispersive shear wave propagation relies on phase speed analysis, which fits a theoretical relationship to the measured frequency-dependent wave velocity. However, this approach is challenged when applied to soft tissues with complex geometries and/or advanced material models, as there are no theoretical dispersion equations available...
Shear wave inspection is generated from mode conversion of longitudinal waves, using a selected, angled wedge positioned between the transducer and the test specimen. However, in certain scenarios where access is restricted the combination of the transducer and the wedge can be too cumbersome for in situ deployment. In this work, a low profile, linear ultrasound array transducer is proposed to generate...
We present finite element (FE) modeling approaches of ear mechanics including 3-dimensional (3D) reconstruction of the human middle and inner ear. Specifically, we demonstrate a semi-automatic methodology for the 3D reconstruction of the inner ear structures, a FE harmonic response model of the middle ear to predict the stapes footplate frequency response, a 2D FE slice model of the cochlea for the...
Because of its minimal invasiveness, coil embolization has become a popular way to treat aneurysms. The main problem with this method, however, is the poor understanding of the hemodynamics in the aneurysm after coil embolization. To improve this situation, we used a finite element method and computational fluid dynamics to investigate how hemodynamic parameters depend on the spatial distribution...
Rotary cutting of rotor and stator laminations complements the available methods in the processing of electrical steel sheet. Furthermore, with this process, a technological answer to the production of ever-thinner laminations can be found in which high-speed stamping is reaching its technical limits. This paper explicates a finite element analysis for the rotary cutting process of electrical steel...
Piezoelectric actuator has been used in different applications because of its compact structure compared to magnetic actuators. This paper reports the influence of piezoelectric actuators geometry on the plate vibrating amplitude. Through a Finite Element Method (FEM) approach, we find out the piezoelectric actuator surface area greatly affects the vibrating amplitude. Increasing the piezoelectric...
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