Improved model of void fraction distribution in two-phase flow in the boundary layer

• Autorzy: Mikielewicz D. , Wajs J.
• Języki publikacji: EN

Abstrakty

EN

The aim of present work is investigation focused on experimental verification of forces acting on bubble flowing along the wall and subsequent implementation of the findings into the model of void fraction distribution, developed earlier by one of the co-authors [6]. In experimental investigations the bubble is represented by a solid sphere suspended on a thin string. Authors are convinced that the presented model of a bubble motion captures at least a qualitative behaviour of a bubble in the bubbly flow and will compliment the transverse force balance acting on the bubble. Such transverse balance of forces forms one of equations involved in the model of void fraction developed by Mikielewicz [6]. Presented results of experimental research show periodic character of sphere movement (simplified bubble model) along the wall of vertical channel, which is in line with findings of the experiments preformed on bubbles in vicinity of wall. Sphere trajectory visibly changes, which are caused by non-uniform velocity distribution of fluid around the sphere related to non-uniform pressure field around it, giving in such a way rise to the repelling force. The wall force was introduced to the model of void fraction distribution and improved results were obtained.

Słowa kluczowe

EN

bubble flow; force balance; wall force

PL

przepływ pęcherzykowy; równowaga siły

• Wydawca: Wydawnictwo Instytutu Maszyn Przepływowych PAN ; Komitet Termodynamiki i Spalania PAN
• Czasopismo: Archives of Thermodynamics
• Rocznik: 2006
• Tom: Vol. 27, no. 3
• Strony: 95--116
• Opis fizyczny: Wz., wykr., rys.,Bibliogr. 26 poz.,

Twórcy

autor

Mikielewicz D.

autor

Wajs J.

• Technical Uuniversity of Gdańsk, Faculty of Mechanical Engineering, 80-952 Gdańsk, Narutowicza 11/12

Bibliografia

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