Jure Zevnik (Avtor), Julien Patfoort (Avtor), Juan Manuel Rosselló (Avtor), Claus-Dieter Ohl (Avtor), Matevž Dular (Avtor)

Povzetek

In this work, we experimentally and numerically investigate cavitation bubble dynamics in a thin liquid layer surrounded by gas. We focus on configurations featuring strongly confined bubbles at dimensionless bubble-free surface stand-off distances below unity. Additionally, we impose the condition of null Kelvin impulse, subjecting a bubble to the oppositely equal influence of two opposing free surfaces, resulting in the formation of two convergent water jets. We observe a diverse spectrum of jetting phenomena, including broad jets, mushroom-capped jets, and cylindrical jets. These jets become progressively thinner and faster with lower values, reaching radii as small as 3% of the maximal bubble radius and speeds up to 150 m/s. Numerical results reveal a linear relationship between the jet impact velocity and the local curvature at the bubble region proximal to the free surface. This suggests that the magnitude of bubble deformation during its growth phase is the primary factor influencing the observed fivefold increase in the jet impact velocity in the parameter space considered. Our findings show that bubble collapse intensity is progressively dampened with increased confinement of its environment. As decreases beyond a critical value, the liquid layer separating the bubble and ambient air thins, leading to the onset of interfacial shape instabilities, its breakdown, and bubble atomization. Furthermore, we compare bubbles at zero Kelvin impulse to corresponding anisotropic scenarios with a single free surface, revealing that the dynamics of axial jets until the time of impact is primarily influenced by the proximal free surface. The impact of convergent axial jets at null Kelvin impulse results in local pressure transients up to 100 MPa and triggers the formation of a fast and thin annular outflow in the form of a liquid sheet, affected by the Rayleigh–Plateau and flapping shape instability.

Ključne besede

cavitation;bubble dynamics;free surface;jets;radial spreading;

Podatki

Jezik: Angleški jezik
Leto izida:
Tipologija: 1.01 - Izvirni znanstveni članek
Organizacija: UL FS - Fakulteta za strojništvo
UDK: 532.528
COBISS: 200352771 Povezava se bo odprla v novem oknu
ISSN: 1070-6631
Št. ogledov: 60
Št. prenosov: 14
Ocena: 0 (0 glasov)
Metapodatki: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Ostali podatki

Sekundarni jezik: Slovenski jezik
Sekundarne ključne besede: kavitacija;dinamika mehurčkov;prosta površina;curki;radialno širjenje;
Vrsta dela (COBISS): Članek v reviji
Strani: str. 1-20
Letnik: ǂVol. ǂ36
Zvezek: ǂiss. ǂ6, [article no.] 063340
Čas izdaje: Jun. 2024
DOI: 10.1063/5.0209287
ID: 24505639