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Pojem kavitacija opisuje pojav in aktivnost mehurčkov v kapljevini zaradi padca tlaka. Razumevanje pojava omogoči izogibanje škodi in konstruktivno izkoriščanje destruktivne moči. V nalogi je analiziran vpliv materiala bližnje stene na dinamiko kavitacijskega mehurčka in udarnega vala. S hitro kamero je bil posnet razvoj osamljenega lasersko ustvarjenega mehurčka v mirujoči vodi na različnih oddaljenostih od stekla in pleksi stekla. Predstavljeni so kvantitativni in kvalitativni rezultati računalniške obdelave slik. Čas kolapsa je primerjan s teoretičnim po Rayleigh-Plessetovi enačbi. The term cavitation describes the occurrence and activity of bubbles in a liquid due to a pressure drop. Understanding the phenomenon enables avoiding damage and constructive use of the destructive power. This thesis analyzes the influence of the material of a nearby solid surface on the dynamics of a cavitation bubble and shock wave. The development of a single laser-generated bubble in quiescent water at various distances from glass and plexiglass was recorded with a high-speed camera. Quantitative and qualitative results of computer image processing are presented. The collapse time is compared with the theoretical time according to the Rayleigh-Plesset equation.

Pojem »kavitacija« opisuje pojav parnih mehurčkov in njihove aktivnosti v prvotno homogeni kapljevini. Pojav ima tako dobre kot slabe učinke, a so nekateri izmed njih relativno slabo raziskani. V diplomski nalogi je obravnavan pojav osamljenega mehurčka povzročenega z nenadno nizkonapetostno razelektritvijo. S pomočjo vizualizacije s hitro kamero je zajeto njegovo obnašanje v prostem polju kapljevine. Opazovan je vpliv dolžine elektrod, napetosti na kondenzatorju ter vrste vode na velikost mehurčka. V nadaljevanju so izmerjeni polmeri primerjani z Rayleigh-Plessetovo enačbo. S pridobljenimi rezultati je predstavljeno, kako zagotoviti dobro ponovljivost velikosti mehurčka in kakšno je njegovo odstopanje od diferencialne enačbe. The term “cavitation” describes the appearance of vapor bubbles and their activity in an originally homogeneous liquid. The phenomenon has both good and bad effects, some of which are relatively poorly researched. The diploma focuses on the emergence of a single bubble caused by a sudden low voltage discharge. With the use of visualization, we capture the behavior of a single bubble in a free field of liquid. We then observe the influence of electrode lengths, capacitor voltage and water type on the bubble size and compare the obtained radii with the Rayleigh-Plesset equation. According to the results, the deviation of the bubble behavior from the differential equation is presented, followed by guidelines for good repetition of bubble size measurements.