Title of article :
Study of cavitation phenomena based on a technique for visualizing bubbles in a liquid pressurized chamber
Author/Authors :
Payri، نويسنده , , R. and Salvador، نويسنده , , F.J. and Gimeno، نويسنده , , J. and De la Morena، نويسنده , , J.، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2009
Pages :
10
From page :
768
To page :
777
Abstract :
In this paper, the influence of nozzle geometry on cavitation and near-nozzle spray behavior under liquid pressurized ambient is studied. For this purpose, eight steel drilled plates, with different diameters and degrees of conicity of their holes, are analyzed. A special near-nozzle field visualization technique, using a test rig pressurized with fuel, is used. Due to the difference in refractive index between liquid and vapor phase, bubbles present at the outlet of the orifice are visualized. The pressure conditions at which bubbles start appearing at the orifice outlet are compared with those at which choked flow appears. The results showed that pressure conditions for inception of cavitation obtained in the visualization tests differs from those seen for choked flow (5–8% in terms of cavitation number). In addition to this, the images taken are analyzed to get the angle of the jet formed by fuel bubbles, showing that it increases significantly for those conditions more prone to cavitate. Furthermore, comparison of bubbles generation when increasing or decreasing backpressure indicates the presence of hysteresis in cavitation inception phenomena.
Keywords :
near field , Cavitation , Visualization
Journal title :
International Journal of Heat and Fluid Flow
Serial Year :
2009
Journal title :
International Journal of Heat and Fluid Flow
Record number :
2381755
Link To Document :
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