SimScale CAE Forum

Help with simulation, particle condensing into a single point

It is harder and it takes longer to provide support without full details.To speed up the process and quickly solve your issues this is a reminder to post as much information as you possibly can:

  • A description of the project and what you are trying to achieve
    Modeling a part cooling fan duct to validate that the air is evenly distributed through the outlets and targets right at the tip of the nozzle.

  • An description of what is happening, screenshots or error logs are helpful
    In one of the air channel it seems like the air flow is condensing into a single point causing extremely high velocity. Cannot see where I went wrong and the mesh looks fine.

  • [Important] Always provide a link to your project so that it is easy to find.
    Mosquito Duct CFD -> Compressible 6

(delete this message before posting)


From your latest simulation run, I can see normal levels for velocity, so I guess you’ve already overcome the problem, correct?

Also, for future reference: when velocity levels < 0.3 Mach are expected, make sure to use an “Incompressible” analysis type. You’re dealing with inlet velocities < 4 m/s, so using compressible is definitely not required (and it will add quite a lot of complexity to the set up).


Thanks for the response Ricardopg and the recommendation to use Incompressible. I discovered an extremely small feature on my model that caused the issue, I manually corrected the model and everything started to work correctly.