Study on development and improvement of simulation model for environmental prospect of lake water system

湖泊水系环境前景模拟模型的开发与完善研究

基本信息

批准号：
04660247
负责人：
KUBO Naritaka
金额：
$ 1.09万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1992
资助国家：
日本
起止时间：
1992 至 1994
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04660247/
关键词：
Shallow lake Finite element method Microcystis Long-term muddy water problem Prospect of water environment Eutrophication phenomenon 湖沼水環境差分法吹送流大循環濁水の長期化現象

项目摘要

Two kinds of numerical models were developed for analyzing flow movement in a shallow lake. They are both two dimensional unsteady flow simulation models based on the finite element method, but one is horizontal and the other is vertical.The former model can simulate horizontal water movement and can be used for the analyzes of pollutants' inflow, outflow, diffusion and dilution, if velocities are vertically equally distributed. This model was used for analyzing flow patterns in the Kasumigaura lake and in the lnbanuma lake. It was found that wind effects were primary in the Kasumigaura lake, and pumping operations were strongly effective in the lnbanuma lake. Three dimensional model, which was in the original plan, is not completed, although now approaching final stages through improving its numerical stability.The later model can calculate vertical water movement and is suitable for tracing floating materials, such as microcystis. This model was used to investigate bahaviors of floating materials when dilution water was released in a harbor. Released water may be hot or cold.On the other hand, the long-term muddy water problem in a dam reservoir was studied at field, and in vertical one dimensional simulation model as well. The field study was aimed at gathering hydrological and water-quality data before and after large flood. These data were used to investigate muddy water generating process. One dimensional model was used for examining the effectiveness of curtain wall and bypass channel, which might be used to prohibit inflow water from being mixed with muddy water in a reservoir.Through the above studies, simulation models for solving water envitonmental problems are nearly completed but should be improved to gain a better prospect.

开发了两种数值模型，用于分析浅湖中的流动运动。它们都是基于有限元方法的两个维度不稳定的流动模拟模型，但是一个是水平的，另一个是垂直的。前者可以模拟水平水的运动，如果速度均等分布，则可以用于分析污染物的流入，流出，流出，扩散和稀释。该模型用于分析Kasumigaura湖和Lnbanuma湖中的流动模式。发现在Kasumigaura湖中，风效应是主要的，在Lnbanuma湖中，抽水行动非常有效。原始计划中的三维模型尚未完成，尽管现在通过改善其数值稳定性即将接近最终阶段。后来的模型可以计算垂直水运动，并且适合追踪浮动材料，例如微囊。该模型被用来调查在港口释放稀释水时浮动物料的巴哈维尔人。另一方面，释放的水可能是冷或冷的，在田间和垂直一维模拟模型中研究了大坝水库中的长期泥泞水问题。现场研究旨在在大洪水之前和之后收集水文和水质数据。这些数据用于研究泥泞的水生成过程。一个维度模型用于检查窗帘壁和旁路通道的有效性，这些模型可用于禁止水库中的流入水与泥泞的水混合。通过上述研究，用于解决水令人羡慕的问题的模拟模型几乎已经完成，但应改进以提高前景。