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 ...
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. ...
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 ...
H. Rana ,
 Loughborough University, United Kingdom
This paper presents the investigation into the phenomena during batch reactor vessel mixing comparing agitation equipment; the Rushton turbine and the Marine propeller; in the production of bioethanol by yeast fermentation. The key factors addressed in selecting equipment were fluid vector flow, energy dissipation resulting in shear damage to yeast cells, agitation power consumption, critical ...
Optimization of Extrusion Processes for non-Newtonian high-Viscous Fluids with Wall Slip and Shear Thinning Effects
W. Hoffmann, M. Scholz
SiCo-Solutions, Stuttgart, Germany
Simulation of the flow behaviour of non-Newtonian fluids with high viscosities leads to special material models with specific material parameters. In this presentation, a material model consisting of 4 material parameters describing the flow itself and also the wall slip is presented. The investigations of the flow behaviour are based on COMSOL Multiphysics® using the Modules CFD, Structural ...
D. Sharma , A. Siddiqua ,
 Nitte Meenakshi Institute of Technology, Bengaluru, Karnataka, India
PCR (Polymerase Chain Reaction) is a recent well researched technique which can be employed to obtain an amplified DNA (Deoxyribonucleic Acid). A continuous flow polymerase chain reaction with integrated MEMS based design micro heater for DNA amplification is implemented. Temperature zone is obtained by natural heat conduction rather than making use of typical silicon thermal cycler. Inter ...
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 ...
C.J. Forster, and M.K. Smith
Georgia Institute of Technology, Atlanta, GA, USA
The use of an acoustic field to control the boiling process has the potential to increase the overall rate of heat transfer and delay the critical transition to film boiling. This system is being investigated through the development of a model of a single boiling bubble near a flat, heated, horizontal surface in the presence of an acoustic field. The dynamics of the bubble interface is ...
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 ...
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 ...