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Tasuio September 24, 2002 00:58

vector plot in muliphase?
Hi all,

I use CFX5.5 to learning about mixing between air and water in Tee Junction.I use velocity boundary condition in water inlet(100% water,0%air) and air inlet(100%air,0%water) and average pressuer is uesd in outlet. I have some problem in post-process,

- when plot velocity vector of water,in the air inlet have some vector in this zone but in this zone the volumefraction is zeor. In other,when i plot vector of air,in the water inlet have the arrow in this zone too. I don't understand why in this zone have the vector while in that zone is don't have air or water.

- In initial conition can i use 0% air and 0% water?

- when the slover in finish, in out-file is show the Re. how it calculate? [I mean where of the Re(inler,outlet,etc.) and base in what?(diameter,length,etc)]

I hope that have anyone can help me in that problem.



Michael September 27, 2002 00:00

Re: vector plot in muliphase?
Hi Tasuio, CFX-5 assumes that each control volume contains all fluids. When you specify 100% air, there is actually a very small amount of water as specified by the Minimum Volume Fraction setting. For numerical reasons you can't have exactly 0 for the volume fraction. This shouldn't effect your simulation since the Minimum Volume Fraction is very small. The Reynolds number is based on the length scales that are given near the start of the out file. Hope this helps Mike

Tasuio September 29, 2002 07:17

Re: vector plot in muliphase?
Thank you Michael for you answer.

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