Interaction of two turbulent parallel round jets in the near field of the flow

This paper presents the results of an experimental study of the turbulent structure of the flow of two parallel jets from long round tubes in the near field of the flow. Measurements were performed for distances between the axes of the tubes $s/d = 1.2, 1.8$, and $2.4$ and for Reynolds numbers $\operatorname{Re}=5{,}5\cdot 10^3;1{,}1\cdot 10^{4}$. It is shown that in the near field of the closely spaced twin jets, the longitudinal velocity component on their axis decreases more slowly than in single jets. In this case, the distance between the jets $s/d$ has practically no effect on the transverse scale of the jet and turbulent fluctuations of the longitudinal velocity component. Turbulence anisotropy is practically absent throughout the flow field, except in the outer regions of the jets.