Diffusive and dispersive processes in the aquatic environment and the modeling methods

水生环境中的扩散和弥散过程及其建模方法

• 批准号: 02302065
• 负责人: HAYAKAWA Norio
• 金额: $ 3.46万
• 依托单位: Nagaoka University of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Co-operative Research (A)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02302065/
• 关键词: diffusion; dispersion; turbulent diffusion; diffusion model; hydraulic model; mathematical model; buoyant jet; tidal current

The research study conducted is concerned with diffusive and dispersive processes of various kinds of natural water environment. Through discussion meetingseach study by the participating investigators was compared and the overall view on the diffusive and dispersive processes has been presented. The research results obtained by each investigator are summarized as follows : l. The turbulent wall plume was analyzed with the aid of the k - epsilon turbulence model and the turbulent diffusivity of this flow was obtained. 2. The vertical turbulent diffusivity of the enclosed body of water such as a bay or a lake was formulated and the result was verified. 3. Diffusion and dispersion of turbid matter in a reservoir was studied by both physical and mathematical models. 4. The turbulent diffusivity and dispersion coefficient of composite open channel flow were formulated and verified experimentally. 5. A computer program of simulating the movement of suspended material in the sea was develope … More d to study the relative importance of the diffusive and advective transport. Also, two dimensional FEM and three dimensional FDM simulation programs of the diffusion in the sea were developed. 6. A new scheme of finite difference of the advective terms was developed to give the very high accuracy. Also, a new formulation of the one dimensional dispersion coefficient of the bay was proposed and tested with a number of set of field data. 7. The one dimensional dispersion coefficient of rivers was studied on the basis of the Lagrangian formulation and large number of data collected. Also, a new calculation method of the two dimensional diffusion equation in rivers was formulated using the general natural coordinate system. 8. The turbulent diffusivity in the sea was analyzed using the field data obtained in Tokyo Bay. 9. A good estimate of the horizontal turbulent diffusivity of bays was presented collecting and analyzing the field data. Also, a method and its problem of attaining the similarity of turbulent diffusivity in the bay was presented. 10. A new method of changing the flow structure by modification of the topography of the straits was proposed and demonstrated using the hydraulic model. Less

所进行的研究涉及各种自然水环境的扩散和分散过程。通过讨论会，对参与研究者的每项研究进行了比较，并对扩散和分散过程提出了总体看法。各研究者的研究结果总结如下：借助k -ε湍流模型对湍流壁羽流进行了分析，得到了该流动的湍流扩散系数。2.建立了海湾、湖泊等封闭水体的垂向湍流扩散系数公式，并对公式进行了验证。3.本文用物理模型和数学模型研究了水库中混浊物的扩散和弥散。4.提出了复合明渠水流紊动扩散系数和弥散系数的计算公式，并进行了实验验证。5.编制了一个模拟海洋悬浮物运动的计算机程序 ...更多信息 d研究扩散输送和平流输送的相对重要性。开发了二维有限元和三维有限差分数值模拟程序。6.发展了一种新的对流项有限差分格式，以获得很高的精度。提出了一种新的海湾一维弥散系数公式，并用大量实测资料进行了检验。7.根据拉格朗日方程和大量实测资料，对河流一维离散系数进行了研究。并利用一般自然坐标系建立了河流二维扩散方程的一种新的计算方法。8.利用东京湾的实测资料，分析了海中湍流扩散率。9.通过对实测资料的收集和分析，提出了一个较好的海湾水平湍流扩散系数的估算方法。同时，提出了获得海湾内湍流扩散系数相似的方法及其存在的问题。10.提出了一种通过改变海峡地形来改变水流结构的新方法，并利用水力模型进行了论证。少

项目成果

Y.Nakamura: "Vertical diffusivity in coastal seas" Coastal Engineering in Japan. 34. 57-80 (1991)

Y.Nakamura：“沿海海域的垂直扩散率”日本海岸工程。

T. Komatsu: "Simulation of tidal current and pollutant diffusion in a bay" Proc. Int'l Symp. on Environmental Hydraulics. 847-852 (1991)

T. Komatsu：“海湾中潮汐流和污染物扩散的模拟”Proc。

Y.Iwasa: "Predicting longitudinal dispersion coeffcient in openーchannel flows" Environmental Hydraulics. 2. 505-510 (1991)

Y.Iwasa：“预测明渠水流中的纵向扩散系数”《环境水力学》2. 505-510 (1991)。

N Hayakawa: "The similarity of horizontal diffusvity in the tidal hydraulic model" Proceedings of International Conference on Physical Modeling of Transport and Dispersion. 6B15-6B20 (1990)

N Hayakawa：“潮汐水力模型中水平扩散率的相似性”输运和扩散物理模拟国际会议论文集。

Y.Nakamura and N.N.Hayakawa: "Modelling of thermal stratification in lakes and coastal seas" "Hydrology of Natural and Manmade Lakes",IAHS Publication. 206. 227-236 (1991)

Y.Nakamura 和 N.N.Hayakawa：“湖泊和沿海海域的热分层建模”“天然和人造湖泊的水文学”，IAHS 出版物。