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-   -   volum of fluid VOF (https://www.cfd-online.com/Forums/fluent-multiphase/127032-volum-fluid-vof.html)

BOUALOUACHE December 2, 2013 03:51

volum of fluid VOF
 
hello all,
I have a flow of water plunging into a pool filled with water.
I used the method VOLUM OF FLUID (VOF) and I worked in 2D axisymmetric.
the air entrained by the jet must be in the center of the pool, but I see air bubbles entrained moves towards the walls of the pool.
my question: is someone can explain to me, why I had this moving bubbles towards the walls of the pool? and how I will solve this problem.
I attached a picture of the flow.

Zaktatir December 2, 2013 16:12

VOF: one fluid flow all phases moves with same velocity no slip between bubble and the carrier phase is taken into account... Wrong approach. Only very dilute bubbly flows may be handled with VOF especially when there is no big entrainment and less distortion of the particle path (saffman force, Favre Dispersion, etc..)

Zaktatir December 2, 2013 16:13

by the way when you jet is set to be axis symmetric that will be the first failure since you are neglecting the coanda effect

BOUALOUACHE December 4, 2013 02:52

thank you for your suggestion, i'll take it in consideration ,
so in general , what can you advise me, when i want to simulate a two-fluid flow ?

Zaktatir December 4, 2013 14:35

make tutorials and read some papers books visit webinars make failure failure and failure i am learning everyday something new

mostafa_zeynalabedini February 8, 2014 23:50

VOF model
 
hi every body
I have a question about VOF model in ANSYS FLUENT. The real VOF model have one continuity, momentum and energy equation, and one void fraction advection equation. But in Fluent help (theory guide/multiphase flow/ VOF) there is no continuity equation!!!!!!
Can anyone help me why it does not have continuity equation?


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