The success of flotation operation depends upon the thriving interactions of chemical and physical variables. In this work, the effects of particle size, bubble size, and collector dosage on the bubble loading in a continuous flotation column were investigated. In other words, this work was mainly concerned with the evaluation of the true flotation response to the changes in the operating varia...

An experimental study has been carried out to characterize bubble formation, growth, and detachment mechanisms in a stagnant liquid column. Both bubble frequency and bubble detachment size were measured in different gas flow rates, injector diameters and orientations, submergence height, and liquid properties. Experiments were performed for air injection flow rate ranges between 200 mlph and 12...

We develop a numerical method for solving a free boundary problem which describes shape relaxation, by surface tension, of a long and thin bubble of an inviscid fluid trapped inside a viscous fluid in a Hele-Shaw cell. The method of solution of the exterior Dirichlet problem employs a classical boundary integral formulation. Our version of the numerical method is especially advantageous for fol...

We present a theoretical analysis and experimental demonstration of particle trapping and manipulation around optothermally generated bubbles. We show that a particle located within 500 μm of a surface bubble can be attracted towards a bubble by drag force resulting from a convective flow. Once the particle comes in contact with the bubble's surface, a balance between surface tension forces and...

This report shows methods to fabricate polydimethylsiloxane (PDMS) microfluidic systems for long-term (up to 10 day) cell culture. Undesired bubble accumulation in microfluidic channels abruptly changes the microenvironment of adherent cells and leads to the damage and death of cells. Existing bubble trapping approaches have drawbacks such as the need to pause fluid flow, requirement for extern...

This report shows methods to fabricate polydimethylsiloxane (PDMS) microfluidic systems for longterm (up to 10 day) cell culture. Undesired bubble accumulation in microfluidic channels abruptly changes the microenvironment of adherent cells and leads to the damage and death of cells. Existing bubble trapping approaches have drawbacks such as the need to pause fluid flow, requirement for externa...

Fundamentally based computational models are developed and applied to quantify the removal of inclusions by bubbles during the continuous casting of steel. First, the attachment probability of inclusions on a bubble surface is investigated based on fundamental fluid flow simulations, incorporating the turbulent inclusion trajectory and sliding time of each individual inclusion along the bubble ...

The three-dimensional flow around a hemispherical bubble sliding and growing on a wall in a viscous linear shear flow is studied numerically by solving the full Navier-Stokes equations in a boundary-fitted domain. The main goal of the present study is to provide a complete description of the forces experienced by the bubble (drag, lift and added mass) over a wide range of sliding and shear Reyn...

This paper presents the results from a one-way coupled, Euler–Lagrangian, direct numerical simulation of bubbles injected into a turbulent boundary layer. The Reynolds number of the turbulent boundary layer varies from 420 Re 1800, and the bubble Reynolds number Reb 1. Simulation parameters were chosen to match the experiment of Sanders et al. J. Fluid Mech. 552, 353 2006 investigating bubble-i...

Boiling heat transfer is a key thermal limit in nuclear systems. However, for decades, its modeling has relied on speculative hypotheses and a good dose of empiricism. As researchers now start to develop more mechanistic models, the need for high-quality high-resolution data on the bubble nucleation and growth cycle is increasing. Specifically, nucleation site density, bubble departure diameter...