Error when trying to use LES turbulence model


#1

Hello. I am a bit new to butterfly so I apologise if this is a simple issue. I am using the outdoor example file and am trying to run the simulation using the LES turbulence model. However, I get the following error:

I’ve tried different turbulence models like the default kEqn and WALE in addition to Smagorinsky and still same error. RAS turbulence models work fine.


#2

Did you check line 24 in LES file? That should help you to identify the source of the error.


#3

Thanks for the quick reply. I opened the file in the directory mentioned but this is all it says.


#4

Hello,

I don’t think LES is properly implemented in Butterfly yet. Only the most used RAS models have been properly implemented.

Kind regards,
Theodore.


#5

Oh I see. Do you know if there are any plans to introduce them soon? Or maybe if it is simple enough a way that I could implement it? For part of my thesis I was hoping to compare a few RAS and LES models before deciding which to use.


#6

That would be pretty nice if you could!

The easiest way would be to maybe send us a default / best-practice LES case for outdoor and/or indoor cases. That should be enough to get us going.

Of course, if you want to contribute that directly in code I’m sure @mostapha wouldn’t mind :slight_smile:


#7

OK great. Not totally sure what you mean though. Perhaps, some papers or case studies using LES? I’m very early in my thesis so my experience in butterfly, and in CFD as a whole, is a bit limited but I’m exploring it extensively. I have read a lot of literature involving LES for engineering purposes. I hope to use it for wind load analysis on high-rise buildings with complex geometry. I also have some python experience but i’m sure you guys are leagues ahead of me in that regard :grinning:. Let me know, if anything, what I can contribute, either here or you can contact me privately as well. Thanks.


#8

@errone92 It would be great if by the end of your thesis you had a set of best practices of how to set up LES cases for typical use cases (e.g. for the built environment). Those would definitely be a great addition to Butterfly.

Good luck in your research!

Kind regards,
Theodore.