Introduction: Microbubbles are widely used as contrast agent in diagnostic ultrasound. Recently they have shown good potential for applications in the therapeutic field such as drug delivery to the brain. Recent studies have shown focused ultrasound in conjunction with injected micro-bubbles could temporarily disrupt blood-brain barrier and let therapeutic agents transport into...

We experimentally study the dissolution of carbon dioxide bubbles into common liquids (water, ethanol, and methanol) using microfluidic devices. Elongated bubbles are individually produced using a hydrodynamic focusing section into a compact microchannel. The initial bubble size is determined based on the fluid volumetric flow rates of injection and the channel geometry. By contrast, the bubble...

Fundamentally-based computational models are developed 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 surface as a...

This paper reports on an experimental study of the splitting instability of an air bubble a few centimetres in diameter placed in a sealed cylindrical cell filled with liquid and submitted to vertical oscillations. The response of the bubble to the oscillations is observed with a high-speed video camera. It is found that the bubble dynamics is closely associated with the acceleration of the cel...

A microscale heater array 2:7 mm 2:7 mm in size along with a video camera was used to provide subcooled pool boiling heat transfer measurements at gravity levels ranging from 1.8g to 10 g. The fluid was FC-72 at 1 atm and subcooled by nominally 36 C for all cases. A Terrier–Orion sounding rocket and the KC-135 aircraft were used to provide the microgravity and low-g environments, respectively. ...

The influence of surfactant on the breakup of a prestretched bubble in a quiescent viscous surrounding is studied by a combination of direct numerical simulation and the solution of a long-wave asymptotic model. The direct numerical simulations describe the evolution toward breakup of an inviscid bubble, while the effects of small but non-zero interior viscosity are readily included in the long...

This paper investigates the effect of heat transfer on the motion of a spherical bubble in the vicinity of a rigid boundary. The effects of heat transfer between the bubble and the surrounding fluid, and the resulting loss of energy from the bubble, can be incorporated into the simple spherical bubble model with the addition of a single extra ordinary differential equation. The numerical result...

In the parameter region for sonoluminescence of a single levitated bubble in a water-filled resonator it is observed that the bubble may have an enormous spatial stability leaving it "pinned" in the fluid and allowing it to emit light pulses of picosecond accuracy. We report here observations of a complex harmonic structure in the acoustic field surrounding a sonoluminescing bubble. We show tha...

Related Articles Dynamics of micro-bubble sonication inside a phantom vessel Appl. Phys. Lett. 102, 013702 (2013) Bubble-driven inertial micropump Phys. Fluids 24, 122003 (2012) Effect of viscosity and shear flow on the nonlinear two fluid interfacial structures Phys. Plasmas 19, 122105 (2012) Bubble nucleation on nanoto micro-size cavities and posts: An experimental validation of classical the...

Simulations not seen before compare turbulent mixing rates for ideal fluids and for real immiscible fluids with experimental values for the surface tension. The simulated real fluid mixing rates lie near the center of the range of experimental values. A comparison to theoretical predictions relating the mixing rate, the bubble width, and the bubble height fluctuations based on bubble merger mod...