20.500.12556/RUL-169783 Flow dynamics in cavitation induced micro pumping The micro pumping process driven by the laser induced cavitation bubbles is scalable, requires only optical access and does not require mechanical moving parts. We investigate how the positioning of the cavitation bubble affects the flow dynamics through differently sized holes in a transparent boundary mimicking a microchannel. For normalized standoff distance above 0.8 and normalized hole radius of 0.22 a significant flow through a hole was observed while decreasing the standoff distance a focused reverse flow was formed impeding downward pumping flow. The details of reverse flow formation were investigated. It was found that bubbles generated next to larger holes with a normalized radius of 0.66 also produce reverse flow, however without it impeding the flow through the structure, even at small normalized standoff distances. Simulations were found to agree well with experiments and used to further study the pumping behavior. Indentation on the bottom side of the bubble was found to be the driver of the focused reverse flow in simulations and differences were investigated for various hole radii and standoff distances. For larger hole radii, reverse flow was found to be both weaker and failed to block the entire hole width, permitting pumping behavior. To improve the flow in the pumping direction, additional structures were produced on top of the flat plate with holes. It was found that adding the entry structure to the hole mitigated the effect of the focused reverse flow on the pumping action. cavitation reverse flow micro channel micro pumping rigid boundary counter jet kavitacija povratni tok mikro kanal mikro črpanje trdna meja povratni curek true false true Angleški jezik Slovenski jezik Članek v reviji 2025-06-11 09:38:21 2025-06-11 09:38:35 2026-07-08 04:12:13 0000-00-00 00:00:00 2025 0 0 13 str. art. 111540 Vol. 169 2025 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621 1879-2286 10.1016/j.expthermflusci.2025.111540 238977027 1-s2.0-S0894177725001347-main.pdf 1-s2.0-S0894177725001347-main.pdf 1 800250C99B588C9CFDFA59466DA74911 cb52d0519cf54927554c09cb594f752a2d1568d45dd24a0086417b183965c71f dbd9806c-79e5-11f1-9b0d-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=237232 https://www.sciencedirect.com/science/article/pii/S0894177725001347 0 98963764-4695-11f0-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=211483 Fakulteta za strojništvo 0 0 0