20.500.12556/RUL-161151 Razvoj superhidrofobnih površin z lasersko izdelanimi stebrički za preprečevanje zmrzovanja padajočih vodnih kapljic Development of superhydrophobic surfaces with laser-fabricated pillars for prevention of water droplet impact freezing V okviru zaključne naloge obravnavamo razvoj superhidrofobnih površin z lasersko izdelanimi stebrički za preprečevanje zmrzovanja padajočih vodnih kapljic. Zmrzovanje kapljic, ki padejo na podhlajene površine, je pogost problem na mnogih področjih, vključno z letalskim in ladijskim prometom, daljnovodi, uparjalniki toplotnih črpalk in vetrobranskimi stekli. Za preprečevanje zmrzovanja kapljic se pospešeno razvijajo pasivne metode zaščite v obliki superhidrofobnih površin, ki odbijajo vodne kapljice. Za izdelavo superhidrofobnih površin na aluminijastih vzorcih smo uporabili lasersko obdelavo z nanosekundnimi laserskimi bliski, površine pa smo hidrofobizirali z nanosom tankoslojne prevleke z nizko površinsko energijo. Pri različnim temperaturah površine in hitrostih kapljice smo ovrednotili obstoj odboja kapljice in spremljali njeno širjenje po površini. Ugotovili smo, da tako razmik med lasersko izdelanimi stebrički kot njihove dimenzije pomembno vplivajo na zmožnost odboja vodnih kapljic tudi pri neugodnih kombinacijah parametrov, to je pri nizkih temperaturah površine in visokih hitrostih kapljice. Within this thesis, we are focusing on the development of superhydrophobic surfaces with laser-fabricated pillars to prevent the freezing of water droplets impacting the surface. The freezing of droplets that impact subcooled surfaces is a common problem in many areas, including aviation and maritime transport, power lines, heat pump evaporators, and windshields. To prevent droplet freezing, passive protection methods in the form of superhydrophobic surfaces that repel water droplets are being rapidly developed. For the fabrication of superhydrophobic surfaces on aluminum samples, we used laser processing with nanosecond laser pulses, while the surfaces were rendered hydrophobic by applying a thin low-surface-energy coating. We evaluated the droplet repellency capability and monitored droplet spreading on the surface at various surface temperatures and droplet velocities. We found that both the spacing between the laser-fabricated pillars and the pillar dimensions significantly influence the ability to repel water droplets, especially under unfavorable combinations of parameters, such as low surface temperatures and high droplet velocities. kapljice zmrzovanje superhidrofobne površine laserska obdelava površin odboj kapljic omočljivost površin droplets freezing superhydrophobic surfaces laser surface treatment droplet rebound surface wettability true false false Slovenski jezik Angleški jezik Zaključna naloga 2024-09-07 08:32:15 2024-09-07 08:32:18 2024-12-02 09:12:29 0000-00-00 00:00:00 2024 0 0 XII, 53 f. 2024 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.6.03:621.375.826(043.2) 265432 217187843 37027.pdf 37027.pdf 1 26F25D3E730BC03712F759292C21F849 237d4300d600974000939138b8d9fa6ee5a118139f0cc88e6545556ad483933c e6c87f9d-6ce2-11ef-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=190026 Fakulteta za strojništvo 0 0 0