A sheared wet foam, which stores elastic energy in bubble deformations, relaxes stress through bubble rearrangements. The intermittency of bubble rearrangements in the foam leads to effectively stochastic drops in stress that are followed by periods of elastic increase. We investigate global characteristics of highly disordered foams over three decades of strain rate and almost two decades of s...

This paper deals with the two-state (opening-closing of base pairs) model used to describe the fluctuation dynamics of a single bubble formation. We present an exact solution for the discrete and finite size version of the model that includes end effects and derive analytic expressions of the correlation function, survival probability, and lifetimes for the bubble relaxation dynamics. It is sho...

The non-linear response of a bubble to an acoustic field results in the scattering of sumand difference-frequencies when two frequencies are incident. This has in the past been used to size bubbles. since it is only when the pump frequency. wp' is near the bubble resonance that the non-linear effects are observed. In addition. the subharmonic frequency emitted by the bubble can combine with the...

Measurement of the bubble size distribution in a liquid is very important for cavitation inception studies. In this paper we describe an acoustics based device, the ABS Acoustic Bubble Spectrometer that measures bubble size distributions and void fractions in liquids based on the measurement of sound propagation through the tested liquid. Short monochromatic bursts of sound at different freque...

The degree of shrinkage of particle stabilised bubbles of various sizes, in a polydisperse bubble dispersion, has been investigated in the light of the finite adsorption times for the particles and the disproportionation kinetics of the bubbles. For the case where the system contains an abundance of particles we find a threshold radius, above which bubbles are stabilised without any significant...

bubble size distributions, fractals, nucleation, volcanism Both power law and exponential vesicle size distributions (VSDs) have been observed in many different types of volcanic rocks. We present results of computer simulations and laboratory analogue experiments which reproduce these findings and show that the distributions can be interpreted as the product of continuous bubble nucleation res...

The process of microbubble filtration from blood is complex and highly dependent on the forces of flow and buoyancy. To protect the patient from air emboli, arterial-line filters commonly use a micropore screen, a large volume housing with purpose-built shape, and a purge port to trap, separate, and remove circulating microbubbles. Although it has been proposed that an insufficient buoyancy for...

The performance of microflotation, dispersed air flotation with microbubble clouds with bubble size about 50 µm, for algae separation using fluidic oscillation for microbubble generation is investigated. This fluidic oscillator converts continuous air supply into oscillatory flow with a regular frequency to generate bubbles of the scale of the exit pore. Bubble characterization results showed t...

In bubble-laden flows with large local or global void fraction the distance between bubbles is small so that these interact with a certain probability. During interaction, the bubble can either bounce or undergo coalescence, depending on the nature of the interaction. Coalescence as well as bubble breakup alter the bubble size distribution and consequently change the dynamics of individual bubb...

Modeling and measurement of bubble size in a rotating fluidized bed (RFB) were conducted. The model for predicting the bubble growth in RFB has been proposed based on the following concepts: (i) local centrifugal acceleration and excess gas velocity are considered as the parameters in the radial direction, and (ii) bubble volume flow locally changes depending on the radial distance. Bubbling be...