LES accuracy

September 13, 2005, 14:54

i was wondering if someone could tell me about the time accuracy of LES.

what steps do we need to take to ensure the time steping is accurate enough?

and how important is the temporal accuracy?

September 14, 2005, 10:19

In LES, one filters out the spatial scales and includes models to represent the physics of energy cascade from large to small scales. To maintain temporal accuracy a CFL of 0.2-0.3 is usually employed.

September 14, 2005, 18:29

hi, thanks for answer.

is there any reason why this value of CFL is chosen?

Turbulence · July 18, 2012, 06:23

Hi staustrahltriebwerk

I had tried the refinement box thing. If my locationInMesh is in inlet pipe, then only inlet pipe remains after meshing. If my locationInMesh is in the big cylinder ,then only big cylinder remains. This is what happened in my previous runs. Any idea why?

Thanks
Turbulence.

September 13, 2005, 14:54	LES accuracy	#1
Pimia Guest Posts: n/a	i was wondering if someone could tell me about the time accuracy of LES. what steps do we need to take to ensure the time steping is accurate enough? and how important is the temporal accuracy?

September 14, 2005, 10:19	Re: LES accuracy	#2
agg Guest Posts: n/a	In LES, one filters out the spatial scales and includes models to represent the physics of energy cascade from large to small scales. To maintain temporal accuracy a CFL of 0.2-0.3 is usually employed.

September 14, 2005, 18:29	Re: LES accuracy	#3
Pimia Guest Posts: n/a	hi, thanks for answer. is there any reason why this value of CFL is chosen?

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July 18, 2012, 06:23		#4
Turbulence New Member Deepak Cheekati Join Date: Jul 2012 Location: Chennai, India Posts: 21 Rep Power: 13	Hi staustrahltriebwerk I had tried the refinement box thing. If my locationInMesh is in inlet pipe, then only inlet pipe remains after meshing. If my locationInMesh is in the big cylinder ,then only big cylinder remains. This is what happened in my previous runs. Any idea why? Thanks Turbulence.