A Study on Hydraulic Behaviors of Air-Bubble Plumes in Stratified Water Body

本文采用实验和数值模拟两种方法研究了空气通过孔板进入水体时的水力特性。室内测量的时均速度和湍流的实验数据表明，气泡羽流的基本特征与对称密度羽流或射流的基本特征相似，除了靠近孔口和靠近自由表面的区域。考虑气泡体积变化的数值模拟分析，结合速度分布的实验信息，可以较好地反映作者和Kobus所测得的流场。并将气泡羽流的模拟模型应用于储层的现场实验。数值结果与实测结果的对比表明，该模拟模型适用于水库曝气诱导水流的预测。将水库富营养化过程与上述模拟模型相结合，对水库水质进行了预测。在富营养化模型中浮游植物分为三种。数值结果表明，本文提出的模拟模型至少可以定性地再现水质，但需要进一步的实地观测来验证计算结果。

In this study, hydraulic behabiors of the flow induced by the air dischrged into water body through an orifice are investigated by experimental and nnmerical simulation approaches. The experimental data of time-averaged velocity and turbulence measured in the laboratory show that the fundamental characteristics of the air-bubble plume is similar to the ones of symmetrical density plume or jet, except for the regions near the orifice and close to the free surface. The numerical simulation analysis considering the change of air-bubble volume together with the experimental intormation of the spread of velocity profiles can represent the flow field which have been measured by the authors and Kobus. The simulation model concerning the air-bubble plume is also applied to the reservoir where the field experiments were performed. Comparison between the numerical results and observed ones indicates that the simulation model is applicable to the prediction of flows induced by aeration in reservoirs.The eutrophication process in reservoirs is combined with the simulation model described above and the prediction for the water quality is performed. Phytoplankton is divided into three species in the eutrophication model. Numerical results indicate that the water quality can be reproduced using the simulation model proposed here, at least, qualitatively, though further investigations with field observations are required to verify the calculation results.