权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Analsis on Environmental Hydraulic Dynamics depended on Mixing and Diffusion Phenomenon in Tidal River and Shallow Water

潮汐河及浅水区混合扩散现象的环境水动力分析

基本信息

批准号：
10660229
负责人：
OHASHI Gyozo
金额：
$ 2.3万
依托单位：
Ehime University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

The optimum management for water qualities within river and inland water were researched by the field observations and numerical models.(1). Daily change of water quality (DO,EC,pH,ORP,T-P,POィイD24ィエD2-P,T-N) was investigated by two kinds of measurements at two stations, which were at the up- and down-stream on the gravel river-bed in the Lower Ishite. The results of 1-week-long observations at three times revealed the daily change due to the daily life cycle. Two peaks of water discharge, occurred at around mid-day and mid-night, were observed as a day cycle. The change of water temperature, DO and pH have 24-hour cycles with one peak. Apparent change in the DO and pH of two stations were considered to be due to the effect of the gravel river-bed. The attached algae on the gravel river-bed seem to produce oxygen during the daytime and then DO increases. Moreover, it was found that the gravel bed decreases the amount of T-P. (2). Residual currents in Kii Channel and Ise Bay using a robust diagnostic numerical model were investigated. The computed currents agree well with the data measured by ADCP quantitatively. The residual currents in both Kii Channel and Ise Bay were quasi-geostrophic, which play an important role on the transport of substance in each shallow water. Another study of the distribution changes of phytoplankton and nutrient induced by a submerged structure in vertically two-dimensional steady flow field. A numerical model had the domain (2,000m × 50.5m) and an inflow velocities (0.1 - 0.5m/s). Biological and the advective diffusion domain were in the surface and the bottom layer respectively. (3). Field studies on the polluted water and the sediments under fishery nursery in the Kitanada Bay were carried out by using the water multi-qualities instrument. The deficit oxygen water in bottom circumstance were clarified. Experimental study searched the relationship between ORP-model and the measure of oxygen demand on the surface of bottom material.

采用野外观测和数值模拟相结合的方法，对河流和内河水质的优化管理进行了研究。采用下石石石砾石河床上下游2个测量站的两种测量方法，研究了水质（DO、EC、pH、ORP、T-P、PO φ φ D24 φ φ D2-P、T-N）的日变化。为期一周的三次观察结果揭示了由于日常生命周期而产生的每日变化。两个排水量高峰发生在中午和午夜左右，为一天循环。水温、DO和pH的变化周期为24小时，且有一个峰值。两个站点的DO和pH的明显变化被认为是由于砾石河床的影响。砾石河床上附着的藻类似乎在白天产生氧气，然后DO增加。此外，砾石层降低了T-P的量。（2）. 利用鲁棒诊断数值模型研究了Kii海峡和伊势湾的剩余电流。计算得到的电流与ADCP测量的数据在定量上符合得很好。岐井海峡和伊势湾的残流均为准地转流，对各浅水的物质输送起着重要作用。垂直二维稳定流场中淹没结构引起的浮游植物和营养物分布变化研究。数值模型的区域为2000 m × 50.5m，入流速度为0.1 ~ 0.5m/s。生物扩散区位于表层，平流扩散区位于底层。（3）. 利用水质多质仪对北田湾渔业苗圃污染水体和沉积物进行了实地研究。澄清了海底缺氧水的情况。实验研究了orp模型与底料表面需氧量测量的关系。