Abstract
This paper discusses the applicability of LES to turbulent flows and pressures on a cube in natural wind. Examples of comparative studies between the numerical simulation and the full-scale observations are few. The turbulent flow around a cube is simulated using LES, and compared with the full-scale measurement data for a 6m cube in the meadow by R.P.Hoxey et al. of Silsoe Research Institute. In this research for simulating the characteristics of the natural wind at SRI, we assumed the ratio of the roughness length to the boundary layer thickness to be universal. On the basis of the computed flow patterns, the characteristic of pressure on the roof are discussed. We continue LES computation with the following modification. 1. Higher resolution for the upwind region of a cube as well as near-cube region. 2. For sufficient turbulence intensity of the boundary layer, the larger ratio of the boundary layer thickness to cube height. The instantaneous reattachment is seen and it is expected that the separated flow be reattached by sufficient time passing.
