Help with GeneralExternalFlow

Hi everyone,

I’m a new user of Palabos and I am kinda lost with some of the terms and their meaning in the simulation, or how can they affect to it. I am doing the GeneralExternalFlow tutorial, since I’m interested in evaluating the flow around some bodies, like an sphere, or in the advanced case, an Ahmed Body.

The thing is that, when I use the parameters in the tutorial, everything works fine, but in the moment I change some values, the results I get are weird. So I will post here some doubts and I hope some of you could answer, and see if I can run a proper simulation.

[ul]
[li] In what units it is supposed to be the density and the viscosity?
[/li][li] The “pressure at infinity” is the gauge pressure?
[/li][li] What does the “Iterations for the immersed boundary method” do?
[/li][li] What is the Smagorinsky LES parameter?
[/li][li] If I put a high inlet velocity, the “fluid” at the oulet seems like it bounces back, why does this happen?
[/li][/ul]

These are just some of the questions I got, but I think that it could be really helpful if you can help me. Thank you so much

Best regards,

Alex