Water surface fluctuations of standing waves at the supercritical confluence flow
Fluktuacije vodne gladine stoječega valovanja na sotočju dveh deročih tokov
- Avtorji: Gašper Rak, Marko Hočevar, Franci Steinman
- Citat: Acta hydrotechnica, vol. 30, no. 53, pp. 107-120, 2017.
- Povzetek: Pri deročem toku se pogosto pojavi dvofazni tok, ki ga spremlja močno razgibana, nestacionarna vodna gladina. S klasičnimi merilnimi metodami določitev povprečnega poteka vodne gladine, posebno z večjo prostorsko ločljivostjo, praktično ni možna. Pri analizi sotočja dveh deročih tokov, kjer se oblikuje stoječe valovanje z veliko vertikalno dinamiko gladine, smo za meritve gladine uporabili lasersko skeniranje. Članek prikazuje, da je z obdelavo meritev te brezkontaktne merilne metode mogoče določiti tako srednji potek kot tudi fluktuacije vodne gladine. Rezultati širijo uporabo te merilne metode, ki prinaša pomembne informacije o lastnostih vodnega toka, na številna področja hidrotehnike. Prikazane so tokovne razmere na sotočju, kjer so bile iz izmerjene dinamike vodne gladine v merilnih prerezih za nabor 168 kombinacij dveh dotokov z visokimi vrednostmi Froudovih števil (2 ≤ Fr ≤ 12) določene ovojnice vertikalnih fluktuacij vodne gladine okoli srednje vrednosti. Povezovanje več merilnih prerezov je omogočilo izdelavo razgibane ploskve vodnih gladin z več vrhovi stoječega valovanja na območju sotočja. Zanje so bile razvite fenomenološke zveze med vhodnimi parametri tokov in srednjimi višinami ter fluktuacijami vodne gladine.
- Ključne besede: sotočje, deroči tok, dvofazni tok, fluktuacije vodne gladine, lasersko skeniranje
- Polno besedilo: a30gr.pdf
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