Ultrasonic Atomization of Liquids

Abstract

A theory of ultrasonic atomization of liquid films is presented. It is assumed that exponential growth of surface disturbances ultimately results in the formation of liquid drops, the diameters of which are proportional to the wavelength of the most rapidly growing initial disturbance. The hydrodynamic stability equations of the liquid film are examined, and the most rapidly growing initial disturbances are determined by numerical solution in the unstable region. A resultant correlation between drop size, transducer frequency, transducer amplitude, and liquid-film thickness is obtained. Results are compared to previous theoretical and experimental conclusions.

Measurements of the Size Distribution of Aerosols Produced by Ultrasonic Humidification

“…Plotting the cumulative data on log-probability paper (Figure 3) gives a count median diameter of 1.8 pm and a mass median diameter of 2.9 pm, with computed a, values ([ D,,/D,,]~") of 1.6 and 1 .7, respectively. Boucher and Kreuter (1968) describe a droplet formation equation derived by Lang (1962) and refined by Peskin and Raco (1963). The equation predicts the number median aerodynamic diameter of aerosol droplets produced by an ultrasonic nebulizer for a given liquid surface tension and piezoelectric crystal operating frequency.…”

Electrospray Modifications for Advancing Mass Spectrometric Analysis

“…89,90) Acoustic waves have been used as a simple and alternative means for nebulization and generation of electrospray from liquid samples in MS analysis. [91][92][93] e rst demonstration of using ultrasonic waves for generation of electrospray was conducted by Fenn and co-workers.…”

Luminescence properties of SiO2:Eu3+ nanopowders: Multi-step nano-designing

“…The waves formed by transferring ultrasound oscillations on a given precursor, depending on the superposition conditions, have a complex spatial form that primarily depend on oscillation damping factors in different directions (in the direction parallel or perpendicular to the direction of deformation) and on the forced frequency of the ultrasonic generator [15][16][17][18][19][20][21][22][23][24][25]. Based on the 3D model of capillary standing waves, formed at the meniscus surface, the following expression is obtained:…”

“…The particle size distribution can be estimated by equation [15][16][17][18][19][20][21][22][23][24][25]:…”

“…Processing parameters are chosen in such way to make this interaction constrained to preserve all inherent materials physical properties. Theoretical and experimental background, obtained on the structural and sub-structural designing of a various ceramic systems (alumina, mulite, cordierite, calciumhydroxyapatite, titanium di-oxide, wolfram bronzes doped with a phosphorus, argentum iodate) [15][16][17][18][19][20][21][22][23][24][25], is used in presented work to design and investigate SiO 2 :Eu 3+ powder self-assembling process. The resulting SiO 2 :Eu 3+ powder system is described by experimentally determined distributions of particle and sub-particle sizes, which are further compared to the theoretical calculations.…”