• Seo, Il-Won (Dept. of Civil Engineering, Seoul National Univ.) ;
  • Mohamed S. Gadalrab (Dept. of Civil Engineering, Seoul National University) ;
  • Lyu, Si-wan (Dept. of Civil Engineering, Seoul National University) ;
  • Park, Yong-sung (N4Tech Water Co., Ltd.)
  • Published : 2001.04.01


The theoretical treatments on jets, in which the flow is issuing into a stagnant medium, have been based on Prandtl's mixing theory. In this study, using Prandtl's mixing length hypothesis, a theoretical relationship for the velocity profile of a single round jet is derived. Furthermore, Gaussian expression is used to approximate the theoretical relationship, in which the Gaussian coefficient is assumed to be decreasing exponentially as the flow goes far from the orifice. Two data sets for a single round jet performed by tow different techniques of measurement are used to verify the suggested relationships. The theoretical and Gaussian distribution give close results in spite of the difference in approach. The observed mean velocity distributions are in good agreements with the suggested theoretical and Gaussian distributions.



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