The astonishingly rapid development of the Large-Eddy Simulation technique during the last two or three years, both from the theoretical and applied points of view, have rendered the first edition of this book lacunary in some ways. Three to four years ago, when I was working on the manuscript of the first edition, coupling between LES and multiresolution/multilevel techniques was just an emerging idea. Nowadays, several applications of this approach "ave been succesfully developed and applied to several flow configurations. Another example of interest from this exponentially growing field is the de velopment of hybrid RANS /LES approaches, which have been derived under many different forms. Because these topics are promising and seem to be possible ways of enhancing the applicability of LES, I felt that they should be incorporated in a general presentation of LES. Recent developments in LES theory also deal with older topics which have been intensely revisited by reseachers: a unified theory for deconvolution and scale similarity ways of modeling have now been established; the "no model" approach, popularized as the MILES approach, is now based on a deeper theoretical analysis; a lot of attention has been paid to the problem of the definition of boundary conditions for LES; filtering has been extended to N avier-Stokes equations in general coordinates and to Eulerian time-domain filtering.weiterlesen