Abstract
An artificial air curtain has a possible applicability for the prevention of saline wedge intrusion into a river channel, together with a number of positive effects on ecological system. Salt water intrusion, arriving at the air curtain from the sea, is blown up by the bubble plume until the free surface, where the river flow forces it seawards. Experiments were conducted with different conditions of river flow rate, gas flow rate and density of sea water. The experimental results presented that high gas flow rate for a smaller volume flux and lower density of the salt water is capable of halting salt water intrusion. A k-ε model was employed to analyze the flow field. In the model, bubble motion was analyzed separately, which is then introduced into the momentum equation of water as a drag force. The simulated results achieved satisfactory agreement with experiments, therefrom providing the condition for the successful operation in terms of the volume flux ratios of the salt intrusion volume and the bubble flux, and of the salt intrusion flux and river flow rate.
