Velocity Field Measurements of a Vertical Turbulent Buoyant Jet Using a PIV Technique

Title & Authors
Velocity Field Measurements of a Vertical Turbulent Buoyant Jet Using a PIV Technique
Sin, Dae-Sik; Yun, Jeong-Hwan; Lee, Sang-Jun;

Abstract
The flow characteristics of a turbulent buoyant jet were experimentally investigated using a single-frame PIV system. The Reynolds number based on the nozzle exit velocity and nozzle diameter was about Re=5$\small{\times}$10$\small{^3}$. The instantaneous velocity fields in the streamwise plane passing the jet axis were measured in the near field X/D <11 with and without the temperature gradient. By ensemble averaging the instantaneous velocity fields, the spatial distributions of mean velocity, vorticity, and higher-order statistics up to third order were obtained. The temperature difference of 10$\small{\^{C}}$ does not affect a significant influence to the flow structure in the near field, but the total entrainment rate is increased slightly. The entrainment rate shows a linear variation with the streamwise distance in the region after X/D=5.0.
Keywords
Buoyant Jet;Entrainment;Velocity Field;
Language
Korean
Cited by
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