A Study on the Turbulent Diffusion of Matter and Small Particles by the Random Fourier Modes Method and Stochastic Model

随机傅里叶模态方法和随机模型研究物质和小颗粒的湍流扩散

• 批准号: 09650183
• 负责人: SAKAI Yasuhiko
• 金额: $ 2.05万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09650183/
• 关键词: Fourier modes; Stochastic Process Model; Mixing; Diffsion; Homogenous Turbulence; Cylinder; Rapid Distortion Theory; Turbulent Pipe Flow

This project has been put through according to the initial research plan. The progress and results of the research are summarized in the following,Object (A) Simulation of plume diffusion field around the body in the three dimensional turbulent flow with a uniform mean velocity(l) At first, we investigated the plume diffusion field from a point source developed in the grid-turbulence (in case of no body). The numerical simulations have been made by the random Fourier modes method and a Two-particle stochastic model. The simulation results obtained by both models show good agreements with the experimental results.(2) The turbulent field around the body has been simulated by combining the random Fourier modes method and the rapid distortion theory. By using this simulated turbulent field, the characteristics of a point source plume running perpendicularly into the cylinder have been examined.Furthermore, the reactive mixing layer in the grid-turbulence has been also simulated by the prob … More ability density function (pdf) method. From this time on, an application of this pdf method to the diffusion around the cylinder has been tried.Object (B) Development of kinematic method to simulate the complex turbulent flows by the rapid distortion theory, ant its application to the simulation of diffusion fieldsMainly, the analytical solutions of the rapid distortion theory for the homogeneous turbulent shear flows and axisymmetric contraction/expansion flows have been surveyed. Consequently, it was found that in cases of the axisymmetric contraction/expansion flows there exist the temporally stable solutions, but the solution for the homogeneous turbulent shear flows are temporally unstable.Besides the initial research plan, the diffusion fields of matter in the turbulent pipe flow has been investigated. Further, the fluctuation scalar statistics in the homogeneous isotropic turbulence were estimated from the Lagrangian trajectories of material particles obtained by the direct numerical simulation (DNS). Less

该项目已按初步研究计划实施。本文的研究进展和结果概括如下：（A）三维均匀湍流中物体周围羽流扩散场的数值模拟（1）首先，我们研究了在网格湍流中发展的点源羽流扩散场（无物体情况）。用随机傅立叶模方法和双粒子随机模型进行了数值模拟。两种模型的模拟结果与实验结果吻合较好。(2)采用随机傅立叶模态法和快速畸变理论相结合的方法，模拟了物体周围的湍流场。利用该模拟湍流场，考察了垂直于圆柱面的点源羽流的特性，并利用探针模拟了网格湍流中的反应混合层 ...更多信息 能力密度函数（PDF）方法。目的（B）快速畸变理论模拟复杂湍流的运动学方法的发展及其在扩散场模拟中的应用主要是对均匀湍流剪切流和轴对称收缩/膨胀流的快速畸变理论的解析解进行了综述。结果表明，在轴对称收缩/膨胀流的情况下，存在时间稳定解，而在均匀湍流剪切流的情况下，存在时间不稳定解。利用直接数值模拟（DNS）得到的颗粒的拉格朗日轨迹，估计了均匀各向同性湍流中的涨落标量统计。少

项目成果

Y.Sakai: "Stochastic Simulation of Reactive-Scalar Mixing Layr in a Grid Turbulence by the PDF Method" Proceedings of the 3rd ASME/JSME Joint Fluids Engineering Conference. (to be published.). (1999)

Y.Sakai：“通过 PDF 方法对网格湍流中的反应标量混合层进行随机模拟”第三届 ASME/JSME 联合流体工程会议论文集。

J.C.Vassilicos: "Kinematic Simulations" Advances in Turbulence VII (Proceedings of the 7th European Turbulence Conference). 581-584 (1998)

J.C.Vassilicos：“运动学模拟”湍流 VII 进展（第七届欧洲湍流会议论文集）。

Y.Sakai: "Turbulent Diffusion in the Pipe Flow by the Stochastic Lagrangian Model" Advances in Turbulence VII (Proceedings of the 7th European Turbulence Conference). 547-550 (1998)

Y.Sakai：“随机拉格朗日模型在管流中的湍流扩散”《湍流 VII 进展》（第七届欧洲湍流会议论文集）。

Y.Sakai: "Stochastic Simulation of the Scalar Diffusion Field in the Turbulent Pipe Flow" Proceedings of the 47th Annual Meeting of TOKAI brunch of JSME. No.983-1. 125-126 (1998)

Y.Sakai：“湍流管流中标量扩散场的随机模拟”JSME 第 47 届 TOKAI 早午餐年会论文集。

鈴木健: "ランダムフーリエモード法による減衰乱流中の変動スカラ場の数値シミュレーション" 日本機械学会第75期通常総会講演会講演論文集. (発表予定). (1998)

Ken Suzuki：“使用随机傅里叶模式方法对阻尼湍流中的脉动标量场进行数值模拟”日本机械工程师学会第 75 届普通大会记录（待发表）。