Central to several widely encountered phenomenon in nature is the process of bubble entrainment in a liquid pool as a plunging jet impinges on-to its surface. A look around reveals the presence of this phenomenon in daily chores ranging from filling of a glass of water using tap to several chemical reactions, such as mineral flotation, steel teeming process and gas absorption. Our work involves the experimental and numerical investigation of the this phenomenon. Possible outcomes due to jet impingement in a pool have been identified as smooth free surface without entrainment or formation of rigorous bubble cluster below the jet-pool contact. Triangular entrained region is found to be a three dimensional association of disconnected bubble population continuously breaking and making with neighbors. Using high-speed imaging, the initiation of the entrainment phenomenon as well as temporal and spatial variations of the bubble population are established. A correlation for prediction of maximum entrained height for a range of jet diameters and lengths is proposed. During entrainment, free surface of the pool shows undulations which subsequently releases droplets of different sizes around the jet. Along side, a conductivity probe has also been used to examine the probabilistic presence of bubble at a given height in the liquid pool.
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