Effervescent tryska - časové a prostorové změny struktury spreje

Effervescent atomizer - temporal and spatial variations of spray structure

conference paper

en

An effervescent atomizer generated spray is studied using combined PIV-PLIF technique. Liquid phase concentration, 3D velocity and thus mass flux distribution in a plane perpendicular to the spray axis is measured. Spatial and temporal fluctuations of the liquid concentration and mass flux are evaluated. Both fluctuations show annular spatial distribution with low value near spray axis and maximum close to the spray edge. A transparent Plexiglass atomizer is used in this study. Internal atomizer two-phase flow patterns are predicted by published maps and actual two-phase flow structure is visualized by a digital camera. The atomizer is operated in the range of air gauge pressure 0.1 – 0.5 MPa and Gas-to-Liquid-Ratio 2 – 50%. This range of operation conditions leads to various two-phase flow patterns from bubbly to dispersed. Results show that in case of high GLR the internal mixture is relatively homogeneous and decreasing GLR under certain value can lead to a poor mixing. Influence of operation conditions as well as influence of internal two-phase flow pattern on the fluctuations of the liquid concentration and mass flux is documented. It is seen that the operation of the atomizer under low GLR when an inhomogeneous mixture inside atomizer chamber exists leads to an unsteady spray.

An effervescent atomizer generated spray is studied using combined PIV-PLIF technique. Liquid phase concentration, 3D velocity and thus mass flux distribution in a plane perpendicular to the spray axis is measured. Spatial and temporal fluctuations of the liquid concentration and mass flux are evaluated. Both fluctuations show annular spatial distribution with low value near spray axis and maximum close to the spray edge. A transparent Plexiglass atomizer is used in this study. Internal atomizer two-phase flow patterns are predicted by published maps and actual two-phase flow structure is visualized by a digital camera. The atomizer is operated in the range of air gauge pressure 0.1 – 0.5 MPa and Gas-to-Liquid-Ratio 2 – 50%. This range of operation conditions leads to various two-phase flow patterns from bubbly to dispersed. Results show that in case of high GLR the internal mixture is relatively homogeneous and decreasing GLR under certain value can lead to a poor mixing. Influence of operation conditions as well as influence of internal two-phase flow pattern on the fluctuations of the liquid concentration and mass flux is documented. It is seen that the operation of the atomizer under low GLR when an inhomogeneous mixture inside atomizer chamber exists leads to an unsteady spray.

An effervescent atomizer generated spray is studied using combined PIV-PLIF technique. Liquid phase concentration, 3D velocity and thus mass flux distribution in a plane perpendicular to the spray axis is measured. Spatial and temporal fluctuations of the liquid concentration and mass flux are evaluated. Both fluctuations show annular spatial distribution with low value near spray axis and maximum close to the spray edge. A transparent Plexiglass atomizer is used in this study. Internal atomizer two-phase flow patterns are predicted by published maps and actual two-phase flow structure is visualized by a digital camera. The atomizer is operated in the range of air gauge pressure 0.1 – 0.5 MPa and Gas-to-Liquid-Ratio 2 – 50%. This range of operation conditions leads to various two-phase flow patterns from bubbly to dispersed. Results show that in case of high GLR the internal mixture is relatively homogeneous and decreasing GLR under certain value can lead to a poor mixing. Influence of operation conditions as well as influence of internal two-phase flow pattern on the fluctuations of the liquid concentration and mass flux is documented. It is seen that the operation of the atomizer under low GLR when an inhomogeneous mixture inside atomizer chamber exists leads to an unsteady spray.

dvoumédiová atomizace, Planar Laser-Induced-Fluorescence, Particle Image Velocimetry, struktura spreje

effervescent atomization, Planar Laser-Induced-Fluorescence, Particle Image Velocimetry, spray structure

2006

01.08.2006

Institute for Liquid Atomization and Spray Systems - Japan

Kyoto.,Japan

4-9902774-1-4

Proceedings 10th International Congress on Liquid Atomization and Spray Systems ICLASS-2006

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