Flow Analysis on Near Field of Elliptic Jet Using a Single-Frame PIV

Title & Authors
Flow Analysis on Near Field of Elliptic Jet Using a Single-Frame PIV
Shin, Dae-Sig; Lee, Sang-Joon;

Abstract
Flow characteristics of turbulent elliptic jets were experimentally investigated using a single-frame PIV system. A sharp-edged elliptic nozzle with aspect ratio(AR) of 2 was tested and the experimental results were compared with those of circular jet having the same equivalent diameter($\small{D_e}$). The Reynolds number based on the nozzle exit velocity and nozzle equivalent diameter was about $\small{1{\times}10^4}$. The spreading rate along the major and minor axis are different remarkably. The jet half width along the major axis decreases at first and then increases with going downstream. But along the minor axis the jet width increases steadily. The elliptic jet of AR=2 has one switching points at $\small{X/D_e=2}$ within the near field. Turbulence properties are also found to be significantly different along the major and minor axis planes.
Keywords
PIV;Elliptic Jet;Aspect Ratio;Axis Switching;
Language
Korean
Cited by
References
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