Y. Ou , A. Jaquins-Gerstl , S. G. Weber ,
 Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA
The brain is a heterogeneous porous medium with regions of anisotropy. Measurements of tortuosity (λ) showed that diffusion in gray matter (e.g. striatum) is isotropic (λ = 1.65), whereas it is anisotropic in white matter (e.g. corpus callosum) (λparallel = 1.38, λperpendicular = 1.80)[1-2]. Pressure-driven convection-enhanced delivery (CED) of macromolecules (e.g. drugs) was first described in ...
ABB, Corporate Research, Zürich, Switzerland
The design of modern electric insulation devices for medium and high voltage (HV) applications requires computational work that goes beyond solving just a Laplace equation for the electric potential, and limiting the electric field below critical values. Both field calculation and determination of breakdown limits are often challenges for the development of HV insulation systems. Two examples ...
T. K. Chou, M. Chouteau, M. J. Yi
Department of Civil, Geological & Mining Engineering, École Polytechnique de Montréal, Montreal, QC, Canada
Korea Institute of Geoscience and Mineral Resources, Daejeon, South Korea
Time-lapse electrical resistivity tomography (ERT) method provides a non-invasive way to monitor subtle sub-surface changes caused by water flow such as in an infiltration test. Problems arise when the inversion models contain artifacts due to measurement errors, rapid change in soil electrical property during measurement time, etc. A new approach was developed by Kim et al. (2004) and (2009) ...
V. Babbar, and T. Krause
Department of Physics, Royal Military College of Canada, Kingston, Ontario, Canada
Transient eddy current (TEC) technique is being developed for detection of flaws located at depth within multilayer aluminum structures. The present work involves finite element modeling using COMSOL Multiphysics software to simulate different types of probes by changing some of these parameters in an attempt to generate an output signal of optimum magnitude and shape. Some of the model results ...
M. Alsharif, P. Wallace, D. Hepburn, C. Zhou
Department of Physics, Faculty of Arts, Sebha University, Sebha, Libya
School of Engineering & Computing, Glasgow Caledonian University, Glasgow, United Kingdom
Introduction: Failure in cable insulation is generally preceded by a degradation phase that may last several years. A significant cause of cable system failures is the breakdown of electrical insulation between the electrodes. The operational stresses that occur in cable insulation which include thermal, mechanical and electrical effects will vary with time and can cause degradation due to the ...
J. Güdelhöfer, R. Gottkehaskamp, A. Hartmann
Department of Electrical Machines and Electromagnetic Field Theory, University of Applied Sciences Düsseldorf, Düsseldorf, Germany
This paper shows how a time-dependent and non-linear simulation of the dynamic operation behavior of an induction machine is executed by means of the \"Rotating Machinery\" interface from COMSOL Multiphysics 4.2a. The two-dimensional FEM model is connected to electrical circuits by coupling the physics \"Rotating Machinery\" and \"Electrical Circuit\" interfaces. These circuits include the ...
Using the Electrical Field Analysis for Assessment of the Influence of Paper Insulation on Discharge Initiation in Oil
P. Rozga, D. Hantsz
Technical University of Lodz, Lodz, Poland
Conclusions about the influence of paper insulation on the electrical discharge initiation in mineral oil may be drawn on the basis of experimental studies. However, in some cases, these conclusions may be supported by electrical field analysis. Determination of maximum values of electrical field stress in the vicinity of model electrode setups may bring a new information about initiation ...
Finite Element Modeling of Pulsed Eddy Current Applied to Ferrous and Titanium Fasteners in F/A-18 Airplane Wing Structure
V. K. Babbar, P. R. Underhill, T. W. Krause
Department of Physics, Royal Military College of Canada, Kingston, ON, Canada
Pulsed eddy current (PEC) is being developed to detect stress corrosion cracks between fasteners on the inner wing spars of the F/A-18 Hornet aircraft. The spars are located below a thick carbon/epoxy wing skin, and so cannot be detected by conventional eddy current techniques without disassembling the wing structure. Also, the effectiveness of PEC to detect defects at greater depths is ...
M. A. Saucedo-Espinosa , M. Rauch , B. H. Lapizco-Encinas ,
 Department of Microsystems Engineering, Rochester Institute of Technology, Rochester, NY, USA
 Department of Biomedical Engineering, Rochester Institute of Technology, Rochester, NY, USA
Insulator-based dielectrophoresis (iDEP) employs arrays of electrically insulator posts in a microfluidic device to create dielectrophoretic forces that affect particle movement (Figure 1). The trapping performance of iDEP devices involves a careful balance between electrokinetics (EK) and dielectrophoresis (DEP), where EK is the superposition of electroosmosis (EO) and electrophoresis (EP). The ...
AGH University of Science and Technology
This elaboration presents a pre-study on automatic rotor construction for the flywheel energy storage system dedicated to operate in the levitation mode. The optimization profile model is used as a basic profile source. The 3D flywheel shape is generated on the base of obtained profiles. Eigenfrequencies are calculated to validate the operation on rigid mode. A steel and aluminum based ...