Bubble diameter on detachment in flowing liquidsDiametre des bulles lors du detachement dans les liquides en ecoulementDer abreissdurchmesser von blasen in strömenden flüssigkeitenOтpывHOй диAмeтp пyзыpькA пpи тeчeHии зидкOcтeй
Abstract
An extensive series of measurements of gas bubble diameters on detachment into flowing liquids has been performed. The test liquids were water, water with surface active agent, and ethylene glycol. By use of different surfaces equilibrium contact angles ranging from 22 to 90° were obtained. Based on these results new expressions are proposed for the surface tension and drag forces experienced by a bubble attached to a solid surface.
Résumé
Une série de mesures des diamètres de bulles de gaz lors du détachement a été faite pour des liquides en écoulement. Les liquides utilisés sont l'eau, l'eau avec un agent tensioactif et Péthylène-glycol. Par utilisation de différentes surfaces, les angles de contact varient entre 22 et 90°. A partir de ces résultats, on propose de nouvelles expressions avec la tension superficielle et les forces de trainée pour une bulle attachée à une surface solide.
Zusammenfassung
Es wurde eine ausgedehnte Versuchsreihe über den Blasendurchmesser bei der Ablösung in strömenden Flüssigkeiten durchgeführt. Die Versuchsflüssigkeiten waren Wasser, Wasser mit oberflächenaktiven Zusätzen und Äthylenglykol. Durch die Verwendung unterschiedlicher Oberflächen wurden Gleichgewichtsrandwinkel von 22 bis 90° erhalten. Auf der Grundlage dieser Ergebnisse werden neue Beziehungen für die Oberflächenspannungs- und Widerstandskräfte, die von einer Blase auf eine feste Oberfläche ausgeübt werden, vorgeschlagen.
Реферат
ПpOвeдeHA бOльшAя cepия измepeHий OтpывHыч диAмeтpOв гAзOвыч пyзыpькOв пpи тeчeHии pядA зидкOcтeй: вOды, cмecи вOды c пOвepчHOcтHOAктивHым вeщecтвOм и OтилeH гликOля БлAгOдApя иcпOльзOвAHию pAзличHыч пOвepчHOcтeй пOлyчeHы pAвHOвecHыe yтлты cмAчивAHия Oт 22 дO 90. HA OcHOвAHии peзyльтAтOв измepeHHй пpeдлOзeHы HOвыe выpAзeHия для OпpeдeлeHия cил пOвepчHOcтHOгO HAтязeHия и cOпpOтивлeHия, дeйcтвyющич HA пyзыpeк HA твepдOй пOвepчHOcти.
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