Effect of an entrained air bubble on the acoustics of an ink channel.

Piezo-driven inkjet systems are very sensitive to air entrapment. The entrapped air bubbles grow by rectified diffusion in the ink channel and finally result in nozzle failure. Experimental results on the dynamics of fully grown air bubbles are presented. It is found that the bubble counteracts the pressure buildup necessary for the droplet formation. The channel acoustics and the air bubble dynamics are modeled. For good agreement with the experimental data it is crucial to include the confined geometry into the model: The air bubble acts back on the acoustic field in the channel and thus on its own dynamics. This two-way coupling limits further bubble growth and thus determines the saturation size of the bubble.

[1]  Detlef Lohse,et al.  Phase diagrams for sonoluminescing bubbles , 1996 .

[2]  Detlef Lohse,et al.  Air entrapment in piezo-driven inkjet printheads , 2006 .

[3]  Jianying Cui,et al.  Bubble pulsations between parallel plates. , 2006, The Journal of the Acoustical Society of America.

[4]  Andrea Prosperetti,et al.  Thermal processes in the oscillations of gas bubbles in tubes , 1998 .

[5]  K. Ferrara,et al.  The natural frequency of nonlinear oscillation of ultrasound contrast agents in microvessels. , 2007, Ultrasound in medicine & biology.

[6]  Horng-Show Koo,et al.  LCD-based color filter films fabricated by a pigment-based colorant photo resist inks and printing technology , 2006 .

[7]  J. F. Dijksman,et al.  Hydrodynamics of small tubular pumps , 1984, Journal of Fluid Mechanics.

[8]  Osman A. Basaran,et al.  Small‐scale free surface flows with breakup: Drop formation and emerging applications , 2002 .

[9]  Andrea Prosperetti,et al.  Growth and collapse of a vapor bubble in a small tube , 1999 .

[10]  Q. Jiang,et al.  Oscillatory interaction between bubbles and confining microvessels and its implications on clinical vascular injuries of shock-wave lithotripsy , 2006, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[11]  P. Zhong,et al.  Dynamics of bubble oscillation in constrained media and mechanisms of vessel rupture in SWL. , 2001, Ultrasound in medicine & biology.

[12]  H. Tijdeman.  On the propagation of sound waves in cylindrical tubes , 1974 .

[13]  Andrea Prosperetti,et al.  Growth and collapse of a vapor bubble in a narrow tube , 2000 .

[14]  Chris Williams,et al.  Ink-jet printers go beyond paper , 2006 .

[15]  Andrea Prosperetti,et al.  Entrapped air bubbles in piezo-driven inkjet printing: Their effect on the droplet velocity , 2006 .

[16]  Paul A. Dayton,et al.  Microbubble oscillation in tubes with diameters of 12, 25, and 195 microns , 2006 .

[17]  Andrea Prosperetti,et al.  The natural frequency of oscillation of gas bubbles in tubes , 1998 .

[18]  H. Le,et al.  Progress and Trends in Ink-jet Printing Technology , 1998, Journal of Imaging Science and Technology.

[19]  K. Hynynen,et al.  Resonance frequency of microbubbles in small blood vessels: a numerical study. , 2005 .

[20]  Marios M. Fyrillas,et al.  Dissolution or growth of soluble spherical oscillating bubbles: the effect of surfactants , 1995, Journal of Fluid Mechanics.

[21]  J. Womersley.  Method for the calculation of velocity, rate of flow and viscous drag in arteries when the pressure gradient is known , 1955, The Journal of physiology.