Numerical Modeling of Powder Flow During Coaxial Laser Direct Metal Deposition: Comparison Between Ti-6Al-4V Alloy and 316L Stainless Steel
S. Morville, M. Carin, D. Carron, P. Le Masson, M. Gharbi, P. Peyre, R. Fabbro
Université de Bretagne-Sud/UEB-LIMATB, Lorient, France
PIMM, Arts et Métiers ParisTech, Paris, France
This paper presents a 3D numerical model to predict the whole process of coaxial powder flow, including the particle stream flow in and below the nozzle and also the laser-particle interaction process. The Particle Tracing Module of COMSOL Multiphysics is used to solve the coupled momentum transfer equations between the particle and gas phase while incorporating particle temperature evolution. A ...
N. Gurler, Y. Ziya Ider
Department of Electrical and Electronics Engineering, Bilkent University, Ankara, Turkey
Designing a Radio Frequency (RF) birdcage coil used in Magnetic Resonance Imaging (MRI) at high frequencies where the wavelength is comparable with the coil dimensions is a challenging task. Before construction of the coil, not only calculating the capacitance value which is necessary for the coil to resonate at the desired frequency but also geometrically modeling the coil in a 3D simulation ...
Dipartimento di Ingegneria Industriale, Università degli Studi di Parma, Parma, Italy
The work is focused on the numerical analysis of forced convection in curved tubes investigating the correlation between the heat transfer and friction factor enhancement and the effects of the wall curvature. The analysis was performed by integrating the continuity, momentum and energy equations within COMSOL Multiphysics. The local Nusselt number reaches values higher than the ones expected for ...
Sulfur Deactivation Effects on Catalytic Steam Reforming of Methane Produced by Biomass Gasification
P. Sadooghi, R. Rauch
Vienna University of Technology, Vienna, Austria
Sulfur, which is incorporated in the biomass structure, is released into the product gas during gasification as hydrogen sulfide. Hydrogen sulfide is known to deactivate nickel based steam reforming catalysts by chemisorption on the metal surface during steam reforming process. Desulfurization has a negative effect on the process efficiency therefore steam reforming has to be run without ...
U. N. Mughal, M. S. Virk
Narvik University College, Narvik, Norway
Atmospheric ice is a very complex material with varying electrical properties due to different polymorphs of ice itself. Also, if the medium to be considered is snow, then density becomes an additional parameter because it is a mixture of three dielectrics water, ice and air. The permittivity and loss tangent of naturally occurring ice and snow shows lot of variation at different conditions ...
Wenger Engineering, Ulm, Germany
The ampacity of a cable depends on the cross section of its conductor. When selecting a cable design for a specific application it is of interest to choose the lowest possible conductor cross section in order to reduce material costs. Therefore an exact calculation of the ampacity is necessary (it is usually limited by the thermal resistance of the insulating cable materials). Commonly the ...
G. Cerretti, J.-C. Gomez-Lavocat, K. Vynck, D.S. Wiersma
European Laboratory for Non-Linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
The Institute of Photonic Sciences (ICFO), Mediterranean Technology Park, Castelldefels, Spain
Istituto Nazionale di Ottica (INO), National Research Council (CNR), Florence, Italy
Liquid-crystal elastomers (LCEs)  have attracted a great attention in recent years due to their high potential in a wide range of applications, from microfluidics components  to artificial muscles . The photo-mechanical response of LCEs is due to their constitutive photo-sensitive molecules, which change shape when absorbing part of the incident light. These microscopic deformations can ...
Current Density Distribution and Material Removal Behavior on the Graphite/Iron-matrix Interface in Cast Iron Under Pulse Electrochemical Machining Conditions
O. Weber, R. Kollmannsperger, D. Bähre
Center for Mechatronics and Automatization, Saarbrücken, Germany
Institute of Production Engineering, Saarland University, Saarbrücken, Germany
The Pulse Electrochemical Machining is especially suitable for the precise production of complex geometric contours with high precision and high surface quality demands in workpieces in series manufacturing. During this process, the negative structure of an electrode is copied to the workpiece without sub-surface damages. An adequate knowledge of the current density distribution and thus of the ...
L. Mongibello, N. Bianco, R. Fucci, F. Moscariello
ENEA - Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Portici, Italy
DETEC - Università degli Studi di Napoli Federico II, Napoli, Italy
This work focuses on the numerical analysis conducted on the prototype sensor for the measurement of highly concentrated radiative heat fluxes, based on an inverse heat transfer method, realized at the ENEA Portici Research Center in collaboration with the DETEC department of the University of Naples Federico II. The estimates of highly concentrated radiative heat fluxes on the target surface of ...
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 ...