Doklady PhysicsDoklady PhysicsДоклады Российской академии наук. Физика, технические науки2686-74003034-5081The Russian Academy of Sciences69784510.7868/S3034508125050116МЕХАНИКАResearch ArticleTRANSITION FROM STRATIFIED TO ANNULAR FLOW IN A FLAT MINICHANNEL AT HIGH LIQUID AND GAS VELOCITIESПЕРЕХОД ОТ РАССЛОЕННОГО ТЕЧЕНИЯ К КОЛЬЦЕВОМУ В ПЛОСКОМ МИНИКАНАЛЕ ПРИ ВЫСОКИХ СКОРОСТЯХ ЖИДКОСТИ И ГАЗАMungalovA. S.МунгаловА. С.a.mungalov@alumni.nsu.ruKonkinD. Yu.КонкинД. Ю.KarchevskyA. L.КарчевскийА. Л.KabovO. A.КабовО. А.Kutateladze Institute of Thermophysics, Siberian Branch of the Russian Academy of SciencesИнститут теплофизики им. С.С. Кутателадзе Сибирского отделения Российской академии наук150920255241VOL 524, NO1 (2025)ТОМ 524, №1 (2025)697505122025Copyright ©; 2025, Russian Academy of SciencesCopyright ©; 2025, Российская академия наук2025Russian Academy of SciencesРоссийская академия наукhttps://jdigitaldiagnostics.com/2686-7400/article/view/697845

This study is devoted to the experimental investigation of the transition from stratified to annular flow in a flat minichannel at various gas and liquid velocities, including condition of turbulent flow. Water and air were used as the components of the two-phase flow. It was found that the transition to annular flow at high liquid and gas flow rates occurred not only due to side wall wetting, as reported in the literature, but also due to drop entrainment. Moreover, when the influence of side wall wettability was eliminated by placing fibers into recesses near the side walls of the minichannel, the transition to annular flow at high liquid and gas flow rates occurred solely due to drop entrainment from the wavy gas-liquid interface, which, to the best of the authors' knowledge, was obtained for the first time.

Работа посвящена экспериментальному исследованию перехода от расслоенного режима к кольцевому в плоском миниканале при различных скоростях газа и жидкости, включая условия турбулентного течения. В качестве компонентов двухфазного течения использовались вода и воздух. Установлено, что переход к кольцевому режиму при высоких расходах фаз происходит не только из-за смачивания боковых стенок, как показано в литературе, но и уноса капель от межфазной границы. Более того, при устранении влияния смачиваемости боковых стенок за счет установки продольных хорошо смачиваемых тонких цилиндров в углубления вблизи боковых стенок миниканала переход к кольцевому режиму при высоких расходах жидкости и газа происходил только за счет уноса капель от волновой межфазной границы, что, насколько известно авторам, установлено впервые.

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