Improvement of Water Quality in Lakes and Reservoirs by Air-Bubble Plumes

Abstract

In recent years, air-bubble plumes have been applied as a hydraulic measure for water quality improvement to some Japanese water supply reservoirs. In order to optimize the hydraulic design of air-bubble systems, the relationship between mixing efficiency and system parameters must be clarified. Based on a review of previous studies, this paper discusses (1) analytical methods of air-bubble plumes in both homogeneous and nonhomogeneous environments, and (2) analytical methods of flow in lakes or reservoirs induced by air-bubble plumes. Examples of prototype designs for destratification and hypolimnetic aeration are presented. Future studies needed are summarized finally.