CFX-particle flow

 Register Blogs Members List Search Today's Posts Mark Forums Read

 August 2, 1999, 07:08 CFX-particle flow #1 Eve Chapper Guest   Posts: n/a Hi, I'm using CFX and in the command file I would like to add 3-micrometer particles (of yeast) into a flow stream of water. I've tried following the example in the book but I'm extremely lost. Can anyone out there please help. Thanks Eve

 August 2, 1999, 08:53 Re: CFX-particle flow #2 Patrick Godon Guest   Posts: n/a Hi there, I am not working with CFX and I have no clue what is in that software. However, I can try to help with particles in the flow. This is called a two-phase flow. You need to solve for the particle some additional equations where the force that act on a particle is a function of the velocity difference between the flow and the particle. THe equations might have also a different form depending on the density of the particles (if their density is close to the density of the flow then the euqations are not simplified). In the simplest case (the Epstein regime) the particles are just dragged in the flow. There is a drag parameter in the problem with two limiting cases. If the drag is very small then the particles move almost on their own. If the drag is very large, then the particles move with the flow like tracers. I hope this helps, and I hope there is somebody there or here to help you with the CFX part of it. Patrick

 August 3, 1999, 05:29 Re: CFX-particle flow #3 yi Guest   Posts: n/a Hi, the following is the relevant part of a command file for particle tracking. You can change it accordingly and add it into your command file. Hope that it will help. Yi ---------------------------------------------------------- >>CFX4 #CALC NP=100; /* number of particles */ #ENDCALC >>OPTIONS PARTICLE TRANSPORT >>MODEL DATA >>PARTICLE TRANSPORT MODEL >>MODEL CHARACTERISTICS NUMBER OF PARTICLES 100 NUMBER OF ITERATIONS 1 CROSS SECTION FACTOR 1.0000E+00 SURFACE AREA FACTOR 1.0000E+00 DROPS >>INTEGRATION PARAMETERS TIME LIMIT 5.0000E+00 COEFFICIENT OF RESTITUTION 0.0000E+00 >>PARTICLE PROPERTIES BASE PARTICLE DENSITY 1.0000E+03 >>MODEL BOUNDARY CONDITIONS >>PARTICLE TRANSPORT BOUNDARY CONDITIONS POSITIONS IN X DIRECTION #NP*1.0e-4 POSITIONS IN Y DIRECTION #NP*0.130 POSITIONS IN Z DIRECTION #NP*3.0 INITIAL PARTICLE DIAMETERS #NP*3.0e-6 PARTICLE MASS FLOW RATES #NP*1.0E-6 U VELOCITY #NP*6.0 V VELOCITY #NP*0.0 W VELOCITY #NP*0.0

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post payam_IUST FLUENT 1 October 15, 2009 17:16 saii CFX 2 September 18, 2009 08:07 F. Bhuiyan CFX 3 August 9, 2009 23:28 Ihsan CFX 9 January 15, 2008 19:50 flybird FLUENT 0 May 24, 2007 10:44

All times are GMT -4. The time now is 00:51.