乱流構造に基づくSGSモデルを用いた微気象場のLES計算手法の開発

Abstract

The diffusion phenomena of heat and pollutants caused by the heat convection or the turbulence flow in the non-isothermal field is one of the important phenomena concerned with the local heavy rain or air pollution. The large eddy simulation (LES) which can analyze the turbulence structures in the non-isothermal field is considered as one of the effective means for investigating those phenomena. The purpose of this study is to develop a computational method for the large eddy simulation of the turbulent transport of heat and vapor in the micrometeorological field. The equations for conservation of mass, momentum, heat and vapor are discretized by the finite volume method using a generalized curvilinear coordinate system, and the coherent-structure Smagorinsky model is applied to a subgrid-scale model. The large eddy simulations of the turbulent channel flow, the backward facing step flow, the Reyleigh-Bénard convection and the shallow cumulus convection are carried out to demonstrate the validity of this method.