Whose programming is more difficult?DNS or LES?

January 6, 2006, 10:09

I want to choose one requiring less effort.

January 6, 2006, 10:11

DNS, by definition.

January 6, 2006, 10:40

DNS is computationally expensive and therefore requires perhaps parallelisation and the handling of much data.LES is cheaper and probably can be carried out on a single fast PC; no parallelisation is then required.

Thus, developing and running a DNS code does not have to be easier than developing and running an LES code ...

January 6, 2006, 11:20

DNS, programming cheap (by definition as Guillaume said) but computationally very expensive

LES with classic Smagorisky, programming and computationally cheap (but with little accuracy)

Regards

Renato.

January 6, 2006, 11:24

DNS: programming cheap (by definition as Guillaume said) but computationally very expensive

LES + classic Smagorisky and without any wall law: programming and computationally cheap (but with little accuracy)

Regards

Renato.

January 6, 2006, 17:23

I understand the arguments about intensive computation for DNS with respect to LES but, as one does not use LES and DNS for the same cases (dimensions, turbulence intensity), in practice, one barely manages to resolve the inertial range of the turbulence spectrum without a fine mesh. Thus, LES is expensive as well.

January 6, 2006, 10:09	Whose programming is more difficult?DNS or LES?	#1
Adonis Guest Posts: n/a	I want to choose one requiring less effort.

January 6, 2006, 10:11	Re: Whose programming is more difficult?DNS or LES	#2
Guillaume Guest Posts: n/a	DNS, by definition.

January 6, 2006, 10:40	Re: Whose programming is more difficult?DNS or LES	#3
tom Guest Posts: n/a	DNS is computationally expensive and therefore requires perhaps parallelisation and the handling of much data.LES is cheaper and probably can be carried out on a single fast PC; no parallelisation is then required. Thus, developing and running a DNS code does not have to be easier than developing and running an LES code ...

January 6, 2006, 11:20	Re: Whose programming is more difficult?DNS or LES	#4
Renato. Guest Posts: n/a	DNS, programming cheap (by definition as Guillaume said) but computationally very expensive LES with classic Smagorisky, programming and computationally cheap (but with little accuracy) Regards Renato.

January 6, 2006, 11:24	Rephrasing	#5
Renato. Guest Posts: n/a	DNS: programming cheap (by definition as Guillaume said) but computationally very expensive LES + classic Smagorisky and without any wall law: programming and computationally cheap (but with little accuracy) Regards Renato.

January 6, 2006, 17:23	Re: Whose programming is more difficult?DNS or LES	#6
Guillaume Guest Posts: n/a	I understand the arguments about intensive computation for DNS with respect to LES but, as one does not use LES and DNS for the same cases (dimensions, turbulence intensity), in practice, one barely manages to resolve the inertial range of the turbulence spectrum without a fine mesh. Thus, LES is expensive as well.

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