Transient Simulation of the Electrolyte Flow in a Closed Device for Precise Electrochemical Machining - new
M. Hackert-Oschätzchen, M. Penzel, M. Kowalick, G. Meichsner, A. Schubert[1,2]
Professorship Micromanufacturing Technology, Technische Universität Chemnitz, Chemnitz, Germany
Fraunhofer Institute for Machine Tools and Forming Technology, Chemnitz, Germany
Precise electrochemical machining (PEM) is an innovative machining technology which results from further development of the electrochemical sinking. PEM works with pulsed low frequency direct current and oscillation of the tool electrode. As part of the project ‘Electrochemical machining of internal precision and micro-geometries with high aspect ratios by process-state-dependent electrolyte ...
R. P. Ruby, G. Kulkarni, U. Kanade
Noumenon Multiphysics Pvt. Ltd., Pune, Maharashtra, India
Oneirix Engineering Laboratories Pvt. Ltd., Pune, Maharashtra, India
Seals or gaskets that are compressed between walls of a container are important to many industrial applications. Understanding the performance of such seals requires an understanding of the microscopic geometry of the sealing surfaces, because the fluid seeps around the undulations of such surfaces. This paper presents strong computational evidence that the microgeometry of such surfaces depends ...
P. Goyal, A. Dutta, and A. K. Ghosh
 Reactor Safety Division, Bhabha Atomic Research Centre, Trombay, Mumbai, Maharashtra, India
Steam drums of a nuclear power plant separate steam from the steam water mixture and sub cooled incoming feed water returns to the reactor. The entire feed water flow is delivered to the steam drum through the feed water sparger. The feed water sparger is provided with number of inverted ‘j’ type lateral tubes to distribute the feed water in the drum for proper mixing with the separated ...
X. Corbella , R. Torres , J. Grau , M. Allué ,
 Escola Universitària d’Enginyeria Tècnica Industrial de Barcelona (Universitat Politècnica de Catalunya), Barcelona, Spain
 Fluid Mechanics Department (Escola Universitària d’Enginyeria Tècnica Industrial de Barcelona - Universitat Politècnica de Catalunya), Barcelona, Spain
 Institut de Robòtica I Informàtica Industrial (Consejo Superior de Investigaciones Científicas – Universitat Politècnica de Catalunya), Barcelona, Spain
PEM Fuel Cells’ durability and performance can be increased using an ejector based hydrogen recirculation system. In this work, a CFD model has been implemented to simulate the flow within an ejector used to recirculate hydrogen in PEM Fuel Cell systems. The model has been validated experimentally and has been used to design and manufacture an ejector that will be implemented in a fuel cell test ...
刘孟杰 , 付芳芳 , 李萌 
动脉瘤破裂是引起蛛网膜下腔出血的一种主要原因。结合 COMSOL Multiphysics® 灵活的几何建模特性以及强大的流体仿真求解能力，本文分别对两组不同大小关系的 MCA 动脉瘤理论模型进行了仿真建模分析。通过模拟分析，获得了动脉瘤球囊体长度和宽度与动脉瘤基底宽度不同比例条件下的动脉瘤速度、压力、壁面切应力（WSS）等参数的变化规律，分析了几何形态与动力学参数之间的关系。模拟结果显示：1、宽颈动脉瘤，瘤体内部旋流强度较之窄颈动脉瘤更强，中心区流速更低，更有利于形成血栓而且顶点处压力更大，更易破裂。2、增大动脉瘤宽度与基底直径的比值，顶点处 WSS 呈非线性增长，但最大值低于 WSS 安全范围的下限值，破裂危险性依然很高；3、动脉瘤宽度与基底直径不同比例下的最大的 WSS 均是主要集中在动脉瘤与载瘤血管结合处（第一剪应力集中区），对血管壁生物组织力学特性影响严重；WSS ...
Understanding the Magnetic Field Penetration in Mesoscopic Superconductors via COMSOL Multiphysics® Software - new
I. G. de Oliveira
Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brazil
Introduction: One of the main characteristic of the superconductors is its diamagnetic response of applied magnetic fields. The superconductors refuse the penetration of magnetic field into its interior, it is the well know Meissner effect, B=0 into the superconductor sample. However when the applied field reach a determined value, the magnetic field can enter. There are two different ways of ...
P. Geraldini ,
 Sogin Spa, Rome, Italy
The aim of this study is to design a new concept of shrouded probe that meets the ISO 2889 requirements and it is suitable for small-ducts installation. In order to reduce the construction costs they have been considered standard stainless steel welding fittings manufactured according to ASME/ANSI specifications. In particular, with the numerical simulations, they have been firstly evaluated ...
I. Bogdanov, S. Jardel, A. Turki, and A. Kamp
Open & Experimental Centre for Heavy Oil, University of Pau, Pau, France
Pore-scale modeling of multiphase flow through porous media is addressed most frequently to improve our understanding of flow and transport phenomena in such settings. It can be used to obtain macro-scale constitutive equations, to assign multiphase flow properties in large scale models, to predict how these properties may vary with rock type, wettability, etc. The description of a physical ...
A. Warning , A. K. Datta ,
 Cornell University, Ithaca, NY, USA
The particle tracking model provided a deeper understanding to the experimental results. The model showed good agreement with experimental data for rotation, transport and attachment. In the attachment model, protrusions create low velocity, low shear regions increasing attachment while holes pull cells toward the surface and increase residence time on the surface increasing attachment rate.
K. Stein, N. Gessner, R. Peterson, A. Wiedmann
Department of Physics, Bethel University, St. Paul, MN, USA
Undergraduate studies are carried out to examine the supersonic flow from an axisymmetric converging-diverging nozzle. Flow in the nozzle is initiated by the rupture of a diaphragm that is positioned between the nozzle and a 1-gallon pressurized air tank. Simulations are carried out in COMSOL Multiphysics® for unsteady, axisymmetric flow with the High Mach Number interface of the CFD Module. ...