THE INFLUENCE OF INLET SWIRLING ON THE AERATION PEROFRMACNE OF JET PUMPS

The effects of introducing inlet driving swirling jet flow in the main jet of jet gas pumps were investigated theoretically in this paper. A theoretical model was established to study the performance of the jet pump with four different inlet swirl elements swirl angles of S = 0°, 15°, 30°, and 45°. Effects of water temperature, jet pump pressure ratio, and jet pump number on the performance of the jet pump were investigated theoretically. The computational results obtained were compared with the experimental results of Hefiiy . The present study was concentrated on the mixing performance of the jet pump to increase the dissolved oxygen DO in tap water under different operating conditions. It was remarkably improved by using swirling flow compared with the non-swirling cases; the required saturation time is decreased and the gas transfer efficiency is increased. The improvement in performance is shown to increase according to the swirl intensity. Good agreement is found between experimental results and predictions.