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Title: Hysteresis in flow patterns in annular swirling jets

Abstract

This study investigates the influence of swirl on the mean cold flowfield of an annular jet with a stepped-conical expansion. Both the axial and azimuthal velocity components are measured using a two component Laser Doppler Anemometry system in forward scattering mode. A detailed description of the radial profiles of both mean axial and azimuthal velocity as well as three components of the Reynolds stress are given. Four different jets are identified as a function of the swirl number: 'Closed Jet Flow', 'Open Jet Flow Low Swirl', 'Open Jet Flow High Swirl' and 'Coanda Jet Flow'. These flow patterns change with varying swirl number and there exists hysteresis when increasing and subsequently decreasing the swirl. Also a method for jet identification based upon pressure measurements is presented to replace the time consuming LDA measurements. (author)

Authors:
;  [1]
  1. Katholieke Universiteit Leuven, Department of Mechanical Engineering, Division of Applied Mechanics and Energy Conversion, Celestijnenlaan 300A, B-3001 Heverlee (Belgium)
Publication Date:
OSTI Identifier:
20880657
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Thermal and Fluid Science; Journal Volume: 31; Journal Issue: 6; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; JETS; HYSTERESIS; REYNOLDS NUMBER; VELOCITY; VORTICES; STRESSES; EXPANSION

Citation Formats

Vanierschot, M., and Van den Bulck, E. Hysteresis in flow patterns in annular swirling jets. United States: N. p., 2007. Web. doi:10.1016/J.EXPTHERMFLUSCI.2006.06.001.
Vanierschot, M., & Van den Bulck, E. Hysteresis in flow patterns in annular swirling jets. United States. doi:10.1016/J.EXPTHERMFLUSCI.2006.06.001.
Vanierschot, M., and Van den Bulck, E. Tue . "Hysteresis in flow patterns in annular swirling jets". United States. doi:10.1016/J.EXPTHERMFLUSCI.2006.06.001.
@article{osti_20880657,
title = {Hysteresis in flow patterns in annular swirling jets},
author = {Vanierschot, M. and Van den Bulck, E.},
abstractNote = {This study investigates the influence of swirl on the mean cold flowfield of an annular jet with a stepped-conical expansion. Both the axial and azimuthal velocity components are measured using a two component Laser Doppler Anemometry system in forward scattering mode. A detailed description of the radial profiles of both mean axial and azimuthal velocity as well as three components of the Reynolds stress are given. Four different jets are identified as a function of the swirl number: 'Closed Jet Flow', 'Open Jet Flow Low Swirl', 'Open Jet Flow High Swirl' and 'Coanda Jet Flow'. These flow patterns change with varying swirl number and there exists hysteresis when increasing and subsequently decreasing the swirl. Also a method for jet identification based upon pressure measurements is presented to replace the time consuming LDA measurements. (author)},
doi = {10.1016/J.EXPTHERMFLUSCI.2006.06.001},
journal = {Experimental Thermal and Fluid Science},
number = 6,
volume = 31,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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