DOI: 10.1615/TSFP6
DNS OF PASSIVE SCALAR FIELD WITH MEAN GRADIENT IN FRACTAL-GENERATED TURBULENCE
RESUMO
Turbulent flow field and passive scalar field in the spatially developing grid-generated turbulence are investigated by means of the direct numerical simulation (DNS). Two types of grids are numerically constructed using a immersed boundary method: the one is a classical biplane square grid and the other is a fractal grid which was firstly used in a wind tunnel by Hurst and Vassilicos (2007) and Seoud and Vassilicos (2007). Two types of passive scalar fields are calculated: the one is a diffusion of a passive scalar with a constant mean gradient and the other is a scalar mixing layer. To ensure the numerical accuracy, fully conservative high order accurate finite different schemes for full staggerd grid system are used. Fundermental flow and scalar fields are presented in this paper.