Dynamics and topology reconstruction of cavitation structures on a sonotrode

Tekoča voda je eden izmed temeljev obstoja življenja, vendar je vse več svetovnega vodovja onesnaženega, hkrati pa potrebe po čisti vodi naraščajo. Čiščenje odpadnih voda je zato nujno potrebno, vendar so obstoječe metode čiščenja le delno učinkovite, energijsko potratne in drage ter vodo sekundarno onesnažujejo. Kavitacija kaže na tem področju velik potencial, vendar je ta kompleksen pojav premalo raziskan za aplikacijo. Posnetki sodobnih hitrih kamer omogočajo dober vpogled v proces kavitacije in obilo možnosti za nadaljnje raziskave. Z več hitrimi kamerami hkrati smo posneli oblak kavitacijskih mehurčkov, ki smo ga ustvarili z ultrazvočno sondo. Nato smo s pomočjo posnetkov poskusili ustvariti 3D model kavitacijskega oblaka. Uporabili smo dve različni fotogrametrični metodi. Ugotovili smo njune prednosti in slabosti pri rekonstrukciji kavitacijskih struktur. Določili smo boljšo metodo in potrebne popravke za izboljšanje 3D modela.Liquid water is one of the cornerstones of life on the Earth, but world’s share of polluted water is getting bigger while the need for clean water is rising every day. Wastewater treatment is therefore strictly necessary but the existing cleaning methods are only partially effective, energy wasteful, costly and they pollute water as well. Cavitation shows great potential in this area but this complex phenomenon has not been researched enough to be applied yet. Modern high–speed cameras’ recordings provide a good insight into the cavitation process and plenty of opportunities for further research. We recorded a cloud of cavitation bubbles, created with an ultrasonic probe, with several high – speed cameras at the same time. Then we tried to create a 3D model of the cavitation cloud using two different photogrammetric methods. We identified their strengths and weaknesses in reconstructing cavitation structures. We presented a better method and necessary corrections to improve the 3D model