Learning Forum

[Tiziano]

Hi, I'm studying droplets and aerosol diffusion in a room with 2 manikin and I've problems with boundaries condition and inlet velocity onthe mouth of "covid" manikin.

I'm using Energy equation, RNG K-epsilon model, DPM model with cone injection of droplets and aerosol (Rosin Rammler distribution).

I want to sneeze and cough with manikin mouth inside the room but HERE my problems begin: I've set fluid zone inside the manikin and wall on the surface, because if I set solid zone inside the manikin I can no longer enter inlet velocity on the mouth. Unfortunately the velocity inlet point inside (see the picture) the body instead of towards the room.

[Rob]

Why do you need to model inside the manikin? Since you've got detached surfaces for the velocity inlet I suspect it's pointing into the manikin volume and not the room.

[Tiziano]

Sure, I don't want to model inside the manikin, my problem is why the inlet is pointing inside the manikin and not outside (inside the room)?
I don't know how to fix this problem

[Rob]

Get rid of the fluid zone inside the manikin, and make sure there's a surface on the manikin where you want to push in flow.

[Tiziano]

Thanks for your help.
I've set solid zone inside the manikin and put the mouth (a circle d = 4 cm) on the face of the manikin but now the program tells me I can't set a velocity inlet from a solid zone.

[Rob]

Why do you want a manikin volume? Unless it's also adding heat into the domain represent it as a void. Also check the cell zone definitions: the air space ought to be a fluid.

[Tiziano]

I want the manikin at a certain temperature (295 or 300 K).
If I set fluid in the cell zone condition then the velocity inlet point inside the manikin and not inside the room. Thank you

[Amine Ben Hadj Ali]

You need to remove the manikin volumes and just keep the walls related to it. At that walls you will set a constant temperature.
To get started import manikin geometries into SpaceCalim or DM, do enclosure to get the fluid volume and use that fluid volume for meshing. If you do not want to go back: in Fluent there is a possibility in removing zones (Fluent Meshing) or deactivating zones (In Fluent solver)

[nada.nouhi]

Hello Tiziano, did you find a solution to the problem ?