|
| |
|
| |
|
|
Tvorba bublin: CFD simulace a experimenty
Havlica, Jaromír ; Bunganič, Radovan ; Růžička, Marek ; Drahoš, Jiří
The motivation of our work is the bubble generation from orifices of a gas distributor in bubble columns. Our interest is in the detail dynamics of bubble formation, namely in investigation of the synchronous and asynchronous modes of bubbling from multiple orifices. We considered the bubble formation both form a needle and an orifice on plate. We approached the problem with both the CFD and experiment.
|
|
| |
|
| |
|
| |
|
|
CFD Flow Simulation in Narrow Channel
Křišťál, Jiří ; Havlica, Jaromír ; Jiřičný, Vladimír
Important multiphase parameters as are volume fraction distribution, phase velocity, or shape and position of the interface are employed in our simulations of the hydrodynamics of gas-liquid flow in a thin-gap channel, 1 mm in width. The volume of fluid (VOF) interface tracking method is used to predict the trajectory and the velocity of a single bubble. The effect of bubble on liquid velocity field is investigated for three bubble sizes. Another goal is the evaluation of the effect of the inlet liquid velocity on bubble motion. The results of this study show different types of dependence of the bubble rise velocity on the inlet liquid velocity for different bubble sizes and also confirm that the ratio of the bubble size to the gap width has to be considered when designing the multiphase micro-reactor systems.
|
|
| |
|
| |
|
|
Diagnostika toku v kanále za náhlým rozšířením.
Tihon, Jaroslav ; Pantzali, M. ; Havlica, Jaromír
The backward-facing step flow is studied by measuring the instantaneous wall shear rate along the channel centerline. A two-strip electrodiffusion probe is applied to provide information on the flow direction in the near-wall region. The wall shear rate profiles behind the step are measured and the position of reattachment point detected. The Reynolds numbers examined (Reh from 30 to 1800) cover the laminar, transient and beginning of turbulent flow regime. The results are found to be in a good agreement with the experimental and numerical data previously published for the same channel geometry (ER=2, AR=25).
|
guest ::
