[Lapidus]

Good Day everybody,

At the moment I am supposed to run a simulation that is the same as the one in the video below. Water droplets impact a wall. Some of them will flow out through an opening at the lower part of the wall, others will be dragged by the gas to another exit. Basically what I want to simulate is the same that can be seen in the video, but adding a small slith next to the corner.

I am having trouble setting this up, haven´t been able to chose the right physics. Neither have I been capable to figure out how the simulation is introducing the droplets in the volume (as a Lagrangian injector?).

Do you have experience with something similar? Do you know what physics are used in the video? Then just let me know, it would be incredibly helpful.

Thank you!!

VIDEO: https://www.youtube.com/watch?v=yvqL5v0KhUQ

[ashokac7]

Originally Posted by Lapidus

Good Day everybody,

At the moment I am supposed to run a simulation that is the same as the one in the video below. Water droplets impact a wall. Some of them will flow out through an opening at the lower part of the wall, others will be dragged by the gas to another exit. Basically what I want to simulate is the same that can be seen in the video, but adding a small slith next to the corner.

I am having trouble setting this up, haven´t been able to chose the right physics. Neither have I been capable to figure out how the simulation is introducing the droplets in the volume (as a Lagrangian injector?).

Do you have experience with something similar? Do you know what physics are used in the video? Then just let me know, it would be incredibly helpful.

Thank you!!

VIDEO: https://www.youtube.com/watch?v=yvqL5v0KhUQ

Yes!! You have to do a Lagrangian injector.
Read the article from Star CCM user guide

"VOF-Lagrangian Impingement and Stripping".

You may need to do "Two way coupling"

More details about the problem is required for further comments.

[Lapidus]

Originally Posted by ashokac7

Yes!! You have to do a Lagrangian injector.
Read the article from Star CCM user guide

"VOF-Lagrangian Impingement and Stripping".

You may need to do "Two way coupling"

More details about the problem is required for further comments.

Thank you for answering! Yes, those physics will work for a simulation similar to this one https://www.youtube.com/watch?v=U2-4WchkQqA.

Yet, in our case, the droplets will hit a wall (dry at first), build a fluid film that with time would become a decent amount of water (VOF). Please note that that water (VOF) is not present at the beginning and all tutorials I have been able to find, always have the water inside the space before the start of the simulation.

Just curious if what I am aiming for can be handled by Star CCM+, computation times don´t matter.

[ashokac7]

SEE THE ANSWERS IN "BLUE"

Originally Posted by Lapidus

Thank you for answering! Yes, those physics will work for a simulation similar to this one https://www.youtube.com/watch?v=U2-4WchkQqA.

Yet, in our case, the droplets will hit a wall (dry at first), build a fluid film that with time would become a decent amount of water (VOF).

You need to do Wall film model too for this. I never saw a case with VOF-Lagrangian-Wall-film. But you can surely do this with Eulerian multi-phase mixture or multi-component. Try VOF first otherwise shift to Eulerian Mixture.
You will have to add VOF-wall film interaction, Lagrangian-VOF interaction and VOF-wall film too.
But search for compatibility of VOF with other models. Otherwise go with other Eulerian Multi-phase.

Originally Posted by Lapidus

Please note that that water (VOF) is not present at the beginning and all tutorials I have been able to find, always have the water inside the space before the start of the simulation.

No this is not the case. You can have no water initially.

Originally Posted by Lapidus

Just curious if what I am aiming for can be handled by Star CCM+, computation times don´t matter.

Yes. This can be handled by Star-CCM+.

VOF is used because of lesser computational time that other Eulerian multi-phase models. So if VOF is giving any compatibility issues then you can always shift.