An Experimental Study of Flow and Oxygen Transfer in Circulation Induced by Air Bubble Plumes.

摘要

Experimental studies of the patterns of circulation and flow induced by aeration from point and line sources submerged in water have been carried out in the laboratory. The influence of the system variables such as aeratior design,water depth and air supply rate,on the induced flow were studied. Efforts were made to extend and clarify the work of previous similar studies for aeration from linear systems. The experimental results are generally in good agreement with those obtained by previous investigators. The ratio of induced water discharge relative to air discharge as a measure of aeration efficiency has been examined and found to increase with manifold submergence depth and decrease with increasing air discharge rate within certain limits. A comparison of the induced flow patterns between the plane water jet and linear air bubble plume system has been made. In addition,an efficiency criterion for comparing these two systems was proposed for a given set of conditions. Measurements are presented of the transfer rate of dissolved oxygen in water from rising air bubbles released from a linear manifold. A simple mass transfer model successfully correlates the data with only one lumped constant which is a function primarily of aeration rate and manifold characteristics.