[yahmed]

Hello Ansys users,

I am trying to model open channel photoreactor (rectangular channel with UV lamp tubes inside it) using VOF model in Fluent.

Models used: K-epsilon turbulence model and VOF open channel selected to capture the free surface.

It is really not working. I have read all the posts in the forum and tried all the tips but nothing is working for me . Either solution is not converging or it seems to be converged but results are not realistic.

Please please please if anyone has experience in the VOF and is willing to help respond to me. I can send the case files and more details about my model.

[Roule]

Originally Posted by yahmed

Hello Ansys users,

I am trying to model open channel photoreactor (rectangular channel with UV lamp tubes inside it) using VOF model in Fluent.

Models used: K-epsilon turbulence model and VOF open channel selected to capture the free surface.

It is really not working. I have read all the posts in the forum and tried all the tips but nothing is working for me . Either solution is not converging or it seems to be converged but results are not realistic.

Please please please if anyone has experience in the VOF and is willing to help respond to me. I can send the case files and more details about my model.

i was also having trouble with vof, and i wasnt very much interested in the free surface as such. i was more concerned with the bottom, so finally i ditched vof and just simulated the flow without vof.

for the free surface, i used the bc 'moving wall' with rel speed =0, shear =0, roughness=0 and the simulations' vel profile and turbulence profiles more or less came up close to my my exp data, except near free surface.

so if u r not very interested in the free surface, u can try the moving wall bc.

hope this helps.

[yahmed]

Originally Posted by Roule

i was also having trouble with vof, and i wasnt very much interested in the free surface as such. i was more concerned with the bottom, so finally i ditched vof and just simulated the flow without vof.

for the free surface, i used the bc 'moving wall' with rel speed =0, shear =0, roughness=0 and the simulations' vel profile and turbulence profiles more or less came up close to my my exp data, except near free surface.

so if u r not very interested in the free surface, u can try the moving wall bc.

hope this helps.

Hello Roule,

Thank you for replying and sorry for my late response.

Actually I was using this option (moving wall' with rel speed =0, shear =0, roughness=0) to get a primary results but my committee advisers asked me to do the VOF model and see if there is a difference in the results. My final target is not to track the free surface but I do particle tracking model along with it so we need to see the differences between the two methods.

Well I hope I can find an end to this nightmare I submitted a request to Ansys support team and hopefully they can help me.

[landerfwc]

Maybe you could upload your case file, it would be easier to find a trouble this way.