Modeling of Kinetics of Air Entrainment in Water Produced by Vertically Falling Water Flow

This study analyzes the process of air entrainment in water caused by vertically falling water flow in the free water surface. The new kinetic model of air entrainment in water was developed. This model includes the process of air entrapment, as well as air removal, water sputtering and resorption. For the experimental part of this study a new method based on digital image processing was developed. Theoretical and experimental methods were used for determining air concentration and its distribution in water below the air-water interface. A new presented mathematical model of air entrainment process allows determining of air bubbles and water droplets concentrations distribution. The obtained theoretical and experimental results were in good agreement.Original Abstract: Atviriu vandenu oro ir vandens sanduros sluoksniuose vyksta ivairus fizikiniai reiskiniai. Is ju yra aktualus vandens aeracijos procesas, nes jis glaudziai susijes su labai svarbiais vandenvalos ir savivalos uzdaviniu sprendimo budais. Darbe aptariama oro itraukimo i vandeni, kuris sukeltas vertikaliai krintancio i atvira vandens pavirsiu vandens srauto, kinetika. Atliktas teorinis ir eksperimentinis tyrimai. Pasiulytas ir sukurtas naujas oro itraukimo i vandeni matematinis modelis, kuris patikrintas eksperimentiskai. Sudarant modeli ivertintas oro itraukimo, jo pasisalinimo per oro ir vandens sandura, vandens laseliu ismusimo ir rezorbcijos procesu vaidmuo. Eksperimentine tyrimo dali sudaro pasiulytas ir isbandytas naujas i vandeni itraukto oro koncentracijos matavimo budas, pagristas skaitmeniniu vaizdu apdorojimo budu. Tiek teoriniu, tiek eksperimentiniu budu nustatytas oro koncentracijos pasiskirstymas vandenyje zemiau oro ir vandens sanduros. Abiem budais gauti rezultatai sutampa ir yra patikimi.