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

Developent of Hypolimnitic Heavier Water Pumping System Using Air Bullets

空气弹重质抽水泵系统的研制

基本信息

批准号：
01850118
负责人：
ASAEDA Takashi
金额：
$ 4.61万
依托单位：
Saitama Universtiy
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B).
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01850118/
关键词：
Hypolimnic water Air bullet Pumping facility De-stratification Reservoir Water quality Vertical convection Fishing field development 成層破壊水質改善鉛直混合

项目摘要

Pumping the hypolimnion water to the free surface is available for the eutrophication protection of the reservoir, de-freezing the harbor, and promoting the marine products. Among various pumping systems, the usage of the air bullet to push up the water through a shroud, hydraulic gun systems is expected to be an efficient system. Here, the system was improved to release the pumped water near the free surface to expect the high entrainment rate at the falling stage.Various experiments, in a homogeneous water and in the stratification, one air-bullet release and the periodical release, were performed to get both bulk and detailed flow structures. Based on these, a physical model was developed for the system both in a homogeneous water and in stratified environments. Then, the following quantities were calculated : pumping rate and velocity as a function of the air flux rate and the length of the shroud, the ambient stratification change with time, etc.. These results were compared with both laboratory and field experiments.Together with the analysis just for this system, compatible systems such as bubble plumes were also studied. At first, experiments were performed both in linearly stratified and in two-layered environments. Then, several important features for the mixing and the pumping rate efficiencies were obtained. In addition, the physical model was developed to analyze the environmental density distribution change. Using these results, the comparison of the bubble plume system and the hydraulic gun system were made in various points. Briefly, the hydraulic gun system becomes better with smaller depth and in case that reliability is important.Finally, as an application of this system, de-eutrophication mechanism by pumping was analyzed. Then, it is proposed that by controlling the thermocline depth with respect to the euphotic layer, the production of photoplankton can be suppressed.

将低层水体抽至自由水面，可用于水库富营养化防治、港口解冻、水产品开发等。在各种泵送系统中，使用空气弹通过护罩将水推起，液压枪系统被期望是一种有效的系统。在此基础上，对系统进行了改进，使其在自由表面附近释放泵水，以期望在下降阶段获得较高的卷吸率，并进行了均质水、分层水、单次空气弹释放和周期性释放等多种实验，以获得整体和详细的流场结构。在此基础上，建立了均匀水体和分层水体中该系统的物理模型。然后，计算了以下量：作为空气通量率和护罩长度的函数的泵送率和速度、环境分层随时间的变化等。这些结果与实验室和现场实验结果进行了比较，并结合该体系的分析，对气泡羽流等相容体系进行了研究。首先，在线性分层和两层环境中进行实验。然后，几个重要的特征的混合和泵的速率效率得到。此外，还建立了物理模型，分析了环境密度分布的变化。利用这些结果，对气泡羽流系统和液压炮系统进行了多方面的比较。简单地说，在水深较小和可靠性要求较高的情况下，液压炮系统的效果更好。最后，作为该系统的一个应用，分析了抽水除富营养化的机理。进而提出通过控制温跃层相对于真光层的深度，可以抑制浮游光生物的生产。