The collapse of a single bubble in an ultrasonic pressure field was studied using a finite-volume 2D axisymmetrical model. Spherical air bubble of resonance size was induced into water near the bottom where it violently collapsed. Maximal pressures, temperatures and velocities, generated during the collapse, were studied with regard to the initial bubble distance from the bottom. The computed bubble shapes were compared to the experimentally observed bubble shapes and a very good agreement was found.
COBISS.SI-ID: 10870299
The goal of the work is to investigate the possibility of cavitation erosion prediction using computational fluid dynamics (CFD) tools only. For that purpose, a numerical process based on a coupling between CFD and an erosion model is presented. The comparison shows that it is possible to use solely CFD tools to predict time evolution of cavitation erosion, including final extent and magnitude, with a very good accuracy.
COBISS.SI-ID: 11009051
As the effects of cavitation in valves are devastating, the choice of the correct valve for a given operating range is crucial. For this, the valve characteristic is needed, whereby one side of the operating range depends on the determination of the incipient cavitation. Visualization method and measurements of pressure oscillations inside the pipeline were simultaneously performed. The visualization method proved efficiency over hydrophone measurements because it is more sensitive to cavitation and the signal is independent of the operating pressure.
COBISS.SI-ID: 10869531
It is known that cavitation on a 2-dimansional hydrofoil with swept leading edge shows evident 3-dimensional effects – in the region where the hydrofoil is the longest, the cavitation is steady and attached, on the other side, where the hydrofoil is the shortest, it is developed and unsteady with cavitation cloud separation. The theory of re-entrant jet reflection on cavity closure line was confirmed by our experimental and numerical study. The paper is the 2nd most downloaded paper in the history of journal Eur. j. mech (source: Science Direct Top 25).
COBISS.SI-ID: 10113307
Due to the extremely long length of experiments, in most studies of cavitation erosion only damage in the incubation period is measured and the final damage is then predicted by extrapolation. A rotating disc test rig and pure copper specimens, as erosion sensors, were used to investigate the correlation between the damage within the incubation period and final mass loss. The results confirmed that the same clear relationship between the damage in the incubation period and the final mass loss rate exists.
COBISS.SI-ID: 10898715