減衰する一様乱流中における変動スカラ場の確率過程モデルによる数値シミュレーション

概要

論文の詳細を見る
This research aims at development of a three dimensional Lagrangian stochastic process model of a particle-pair for predicting the statistics of the scalar fluctuation diffusion field in a non -stationary homogeneous turbulence. In this paper, the three-dimensional stochastic particle-pair model for stationary homogeneous turbulence has been improved so that it is applicable to the non-stationary case. Main points of improvement are as follows; (1) The temporal Lagrangian variation of the velocity fluctuation scale σ_v is incorporated into the Ito's stochastic equation. (2) The effective sphere of the two-particle velocity correlation has been modeled. As a simple example to which this new model can be applied, the scalar fluctuation field of a point source plume in decaying grid-generated turbulence was simulated. The improved model gives a better prediction of the actual scalar fluctuation properties than stationary homogeneous models.
1993-11-25