hi,all! I am new to LES programming,I hope that someone can help me the following questions.

1)Must all LES use wall models? why?

2)Is there any difference between the k-epsi wall functions and LES wall Models? What is it?

3)What is the most easy-to-implement and efficient wall models in LES? How is it numerically implemented? Since I lack the programming experience, the details of numerical implementation is very important for me.

Any comment or some reference is greatly appreciated, thanks

1) No.

2) Yes. The part of the unsteady motion modelled by the two approaches is different.

3) Easiest to implement is placing the first grid point at y+ < 1. Most efficient depends on the dominant physics of what is being simulated.

Describing numerical implementations on a forum such as this is not practical. I would suggest looking at other peoples LES code, reading early LES papers from the 60s and 70s or reading detailed LES reports such as internal reports and PhD theses.

Andy, can you tell me some details about getting such report or thesis through net (address)