Zasnova in preizkus delovanja merilne proge za študije kolapsa osamljenega kavitacijskega mehurčka

Podobnikar, Jure (author), Hočevar, Marko (comentor), Dular, Matevž (mentor)

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.

• Language: Slovenian
• Keywords: kavitacija, dinamika mehurčka, nizkonapetostna razelektritev, vizualizacija, Rayleigh-Plessetova enačba
• Work type: Bachelor thesis/paper
• Organization: FS - Faculty of Mechanical Engineering
• Year: 2017
• PID: 20.500.12556/RUL-94478
• Publication date in RUL: 31.08.2017

Secondary language

• Language: English
• Title: The design and testing of a measuring line for studies of a single cavitation bubble collapse

Abstract

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.

• Keywords: cavitation, bubble dynamics, low-voltage discharge, visualization, Rayleigh-Plesset equation