Air Entrainment by Two-dimensional Plunging Jets : the Impingement Region and the Very-near Flow Field
نویسنده
چکیده
In the developing flow region of a plunging jet, the verynear field (i.e. (x-x1)/d1 < 5) is strongly affected by the entrapment process at the impingement. New quantitative results show that, although the distributions of void fraction and mean velocity have smooth shapes, the flow is highly fluctuating and unstable. At a given location in the mixing layer, the probability distribution function of the mean velocity exhibits two distinctive peaks : the jet impact velocity and the induction trumpet velocity. The water velocity fluctuates between the two characteristic values.
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