Learning Forum

[andres9830]

Hello everyone!

I am trying to simulate and understand the different effects of airflow due to air conditioning when a person inside a conference room sneezes. I would like to know the final positions of the majority of the particles or how many of them end up inside a certain region/volume, e.g. faces of other people.

Some details about my simulation: I am using Discrete Phase with a surface injection from the person's mouth, Rossin-Rammler distribution, and the following data:

V_i=20 [m/s] for the first 0.5 [s]; Material= liquid water; m_dot=19.5E-4 [kg/s]

[Surya Deb]

Hello, nIt is not very clear what you are trying to provide as input. I believe you will be injecting DPM particles from one such marked face and will be looking into DPM post processing variables like Concentration at selected locations like other marked faces?nI am not sure what you mean by if density works for this case.nCan you please elaborate?nRegards,nSDn

[andres9830]

Hello SD! Thanks for your reply.nSorry if I didn't explain the problem properly. I initialized this transient case using the results of SS simulation with an air conditioning velocity inlet at the top and a pressure outlet on the floor.nI am now injecting DPM particles from the mouth of the person located on the left end of the table:nFor this purpose, I created an inlet boundary condition for the air's velocity using the following expression. nI also created an injection of water using a constant velocity of 20 m/s (I couldn't find the option to make it an expression like the inlet condition) and other parameters showed in the following picture. A quick question here: Could this result in both velocities adding up? That would be a problem. nnI am indeed looking for some output variables related to particle count or concentration at the other faces or their proximity (like a sphere of influence or something similar), but I don't know where to look. Maybe I have to use another option in Reports?n I mentioned density because I found it under *Discrete Phase->Histogram->particledensity*, but it turned out it just was the density of the injection material. nAndresn

[Rob]

The velocity won't add up, but check the particle injection velocity as it's a component: a common error is to set a component in the wrong direction. n

[andres9830]

Thanks for the answer, Rob. I'll double-check the normal direction just in case it is in the opposite way.nDo you have any idea on how to get particle concentration on certain regions or volumes of the model? I can't find the option in the Discrete Phase Report. I would really appreciate your help.n

[Rob]

It's a flow side value so you'll find it in the surface and volume integrals. I can't remember if you need interacts with flow switched on. n