Integrated approach to optimization of an ultrasonic processor

In an ultrasonic processor, the input electrical energy undergoes many transformations before getting converted into the cavitation energy, which is dissipated in the medium to bring out the physical/chemical change. An investigation of the influence of free and dissolved gas content of the system on the efficiency of this energy transformation chain is attempted. The results of the experiments reveal that the cavitation intensity produced in the medium varies significantly with the gas content of the system. A unified physical model, which combines basic theories of acoustics and bubble dynamics, has been used to explain the experimental results. An attempt has been made to establish the mechanism of the steps in the energy transformation chain, the involved physical parameters, and interrelations between them. It has been found that the influence of free and dissolved gas content of the medium on the overall energy transformation occurs through a complex inter-dependence of several parameters. Thus, simultaneous optimization of individual steps in the energy transformation chain, with an integrated approach, is necessary for the optimization of an ultrasonic processor. The present study puts forth a simple methodology, with the gas content of the system as manipulation parameter, for this purpose.

[1]  S. Chandrasekaran,et al.  Modelling of a batch sonochemical reactor , 1994 .

[2]  M. S. Plesset,et al.  On the stability of gas bubbles in liquid-gas solutions , 1950 .

[3]  Barber,et al.  Sonoluminescing bubbles and mass diffusion. , 1995, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[4]  Anthony I. Eller,et al.  Rectified Diffusion during Nonlinear Pulsations of Cavitation Bubbles , 1963 .

[5]  Michael J. Miksis,et al.  Bubble Oscillations of Large Amplitude , 1980 .

[6]  Marios M. Fyrillas,et al.  Dissolution or growth of soluble spherical oscillating bubbles , 1994, Journal of Fluid Mechanics.

[7]  Andrea Prosperetti,et al.  Nonlinear bubble dynamics , 1988 .

[8]  L. van Wijngaarden,et al.  On the equations of motion for mixtures of liquid and gas bubbles , 1968, Journal of Fluid Mechanics.

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

[10]  Michael J. Miksis,et al.  Effective equations for wave propagation in bubbly liquids , 1985, Journal of Fluid Mechanics.

[11]  Aniruddha B. Pandit,et al.  Cavitation Reaction Engineering , 1999 .

[12]  L. Crum.  Acoustic cavitation series: part five rectified diffusion , 1984 .

[13]  M. H. Safar,et al.  Comment on Papers Concerning Rectified Diffusion of Cavitation Bubbles , 1968 .

[14]  T. Leighton.  The Acoustic Bubble , 1994 .

[15]  Andrea Prosperetti,et al.  Linear pressure waves in bubbly liquids: Comparison between theory and experiments , 1989 .

[16]  Bradley P. Barber,et al.  Toward a hydrodynamic theory of sonoluminescence , 1993 .

[17]  Aniruddha B. Pandit,et al.  Mapping the cavitation intensity in an ultrasonic bath using the acoustic emission , 2000 .

[18]  C. Bruneel,et al.  Ultrasonic cavitation monitoring by acoustic noise power measurement , 2000, The Journal of the Acoustical Society of America.

[19]  L. Rayleigh.  VIII. On the pressure developed in a liquid during the collapse of a spherical cavity , 1917 .

[20]  M. S. Plesset,et al.  A Nonsteady Heat Diffusion Problem with Spherical Symmetry , 1952 .

[21]  H. G. Flynn.  Cavitation dynamics: II. Free pulsations and models for cavitation bubbles , 1975 .

[22]  Allan D. Pierce,et al.  Acoustics , 1989 .

[23]  Francis E. Fox,et al.  Phase Velocity and Absorption Measurements in Water Containing Air Bubbles , 1955 .

[24]  K. Mørch,et al.  Energy considerations on the collapse of cavity clusters , 1982 .

[25]  H. G. Flynn.  Cavitation dynamics. I. A mathematical formulation , 1975 .

[26]  V. K. Kedrinskii,et al.  On the dynamics of cavity clusters , 1982 .

[27]  L. van Wijngaarden,et al.  One-Dimensional Flow of Liquids Containing Small Gas Bubbles , 1972 .

[28]  I. Hansson,et al.  The dynamics of cavity clusters in ultrasonic (vibratory) cavitation erosion , 1980 .

[29]  E. L. Carstensen,et al.  Propagation of Sound Through a Liquid Containing Bubbles , 1947 .

[30]  L. Foldy,et al.  The Multiple Scattering of Waves. I. General Theory of Isotropic Scattering by Randomly Distributed Scatterers , 1945 .

[31]  J. Macpherson,et al.  The Effect of Gas Bubbles on Sound Propagation in Water , 1957 .

[32]  Lawrence A. Crum,et al.  Sonoluminescence and bubble dynamics for a single, stable, cavitation bubble , 1992 .

[33]  Detlef Lohse,et al.  Inert gas accumulation in sonoluminescing bubbles , 1997, chao-dyn/9708007.

[34]  Milton S. Plesset,et al.  Theory of Rectified Diffusion of Mass into Gas Bubbles , 1961 .