A Lagrangian-Eulerian numerical scheme for the investigation of bubble motion in turbulent flow is developed. The flow is analyzed in the Eulerian reference frame while the bubble motion is simulated in the Lagrangian one. Finite volume scheme is used, and SIMPLEC algorithm is utilized for the pressure and velocity linkage. The Reynolds stresses are modeled by the RSTM model of Launder. Upwind ...

Numerical simulation of bubble growth during pool boiling under the influence of low frequency vibration was performed to understand the influence of common vibrations such as those induced by wind, highway transportation, and nearby mechanical devices on the performance of thermal systems that rely on boiling. The simulations were done for saturated R123 boiling at 277.6 K with a 15 K wall sup...

A characteristic length scale and a time scale are proposed to describe the dynamic growth and departure process of bubbles. A correlation between bubble departure diameter and bubble growth time is established thereby, and a predication formula for bubble departure diameter is suggested by considering the analogue between nucleate boiling and forced convection. # 1999 Published by Elsevier Sci...

A bubbly flow in a vertical miniature tube is analyzed theoretically. The liquid and gas phase are co-current flowing upward. The gas phase is injected via a nozzle whose inner diameter is 0.11mm and it is placed on the axis of the tube. A force balance is applied on the bubble at its detachment. The set of governing equations are solved by use of Mathematica software. The bubble diameter and t...

Nucleate boiling heat transfer coefficients may be strongly reduced by scale formation, even for conditions where the bulk foulant concentration is well below the saturation concentration. Due to the mechanism of micro-layer evaporation, the local concentration at the heat transfer surface can be considerably increased, causing the formation of scale and changes in bubble frequency and bubble d...

We present an experimental analysis of the effects of gravity level on the formation and rise dynamics of bubbles. Experiments were carried out with millimeter-diameter bubbles in the hypergravity environment provided by the large-diameter centrifuge of the European Space Agency. Bubble detachment from a nozzle is determined by buoyancy and surface tension forces regardless of the gravity level...

PURPOSE To compare the big-bubble method using air and liquid as medium of separation for Descemet membrane endothelial keratoplasty (DMEK) lenticule preparation in an eye bank. METHODS Donor corneas (n=20) were immersed in liquid [tissue culture medium (TCM)]. Air and liquid was injected using a 25-gauge needle in the posterior stroma or as near to the stroma-Descemet membrane (DM) phase as ...

This paper develops a procedure for estimation of the rise velocity of a swarm of large gas bubbles in a bubble column operating in the churn-turbulent flow regime. The large bubble swarm velocity is estimated by introducing two correction factors into the classical Davies—Taylor (1950) relation for rise of a single spherical cap bubble in a liquid » b "0.71Jgd b (SF) (AF) . The scale correctio...