# solid-liquid suspension with multi-reference frame

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

 October 25, 2001, 14:47 solid-liquid suspension with multi-reference frame #1 Min-Hua Wang Guest   Posts: n/a Hello, All: Does anybody have experience in the simulation of the stirred tank for solid-liquid suspension with multi-reference frame. Thanks MHW

 October 29, 2001, 05:00 Re: solid-liquid suspension with multi-reference f #2 Alain Guest   Posts: n/a I do, what is your question ?

 October 29, 2001, 12:39 Re: solid-liquid suspension with multi-reference f #3 Min-Hua Wang Guest   Posts: n/a Thanks. I am working on CFD simulation for a stirred tank without baffle blade. I was using Mixsim to setup multi-reference frame and to start single phase simulation. The working fluid is water. The convergency is good. Then I run two-phase simulation withing fluent 4 environement. The solid has 200 micro meter in size and the solid density is 1200 kg/m^3. Volume fraction f solid is about 15%. I run simulation in time transient flow with Eulerian (Granular) model. Also I selected Gidaspow model for granular viscosity. Schuh model is selected for Drag force. The rest I left tehm by default data. How do I justify the final solution. I always observed that the mass residual is very hard to be reduced. The suspension of solid seems to me not developed. How long should I run the simulation. Can you suggest me some experience? Many thanks. MHW

 October 30, 2001, 12:54 Re: solid-liquid suspension with multi-reference f #5 Lanre Guest   Posts: n/a MRF is a steady-state model ONLY, hence, is incompatible with the Eulerian-Granular multiphase model in FLUENT 4. Since you have no baffles, delete the MRF zone and convert to a single frame of reference (See FLUENT 4.4 Users' Guide). Now you can solve the transient mixing and include the Eulerian-Granular model for your multiphase calculations.

 October 30, 2001, 21:56 Re: solid-liquid suspension with multi-reference f #6 Min-Hua Wang Guest   Posts: n/a Now can i use MRF model and Eulerian-Granular model in steady state simulation? Thanks.

 October 31, 2001, 05:28 Re: solid-liquid suspension with multi-reference f #7 Alain Guest   Posts: n/a Yes you can use these models in steady state simulation but convergence can be very difficult to reach. As Lanre said, if your tank has no baffles, you do not need a MRF approach, a single rotating frame will be more correct as it can be use in both transient and steady state. A point about MRF and transient simulation : MRF is a steady state approach so it is true that you may have no significant results if you use it for a transient simulation. Nevertheless you can use it in a transient simulation if you are looking for steady state solution : the intermediate, time dependent, solutions may be not significant, but the converged, steady state solution does. Best regards Alain

 April 30, 2010, 18:22 #8 New Member   Tantular Nurtono Join Date: Mar 2010 Posts: 8 Rep Power: 8 Please observe the solid volume fraction during the iterations. I have problem that the solid volume fractions decreased during the iterations. After the iterations converged, the solid volume fractions is different with the initial value when I patched in the beginning of simulation.

 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 fu-ki-pa OpenFOAM 10 May 1, 2014 16:26 skabilan OpenFOAM Installation 3 July 28, 2009 00:35 allenzhao OpenFOAM Installation 127 January 30, 2009 20:08 Bruno Main CFD Forum 1 January 30, 2007 01:34 Chie Min CFX 5 July 12, 2001 23:19

All times are GMT -4. The time now is 20:01.