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THEORY OF PROCESSES
ArticleName Motion of gas bubble in oscillating gas-saturated liquid
ArticleAuthor Blekhman I. I., Blekhman L. I., Vasilkov V. B., Sorokin V. S., Yakimova K. S.
ArticleAuthorData Blekhman Ilya Izrailevich, Head of Laboratory; iliya.i.blekhman@gmail.com; Blekhman Leonid Ilich, Leading Researcher; Vasilkov Vladislav Borisovich, Leading Researcher; Sorokin Vladislav Sergeevich, Researcher, slavos87@mail.ru; Yakimova Kira Savvovna, Leading Researcher, yakimova_ks@npk-mt.spb.ru; REC «Mekhanobr-tekhnika», Institute of Problems of Mechanical Engineering RAS (Russia).
Abstract

The article is devoted to theoretical and experimental study of gas bubble behavior (compressible particle) in oscillating liquid. This problem is of essential interest with regard to a number of mineral-dressing processes, in particular, flotation process, therefore a considerable number of studies are dedicated to this issue. By the present time, two different mechanisms have been proposed, two explanations of an experimentally registered effect of gas bubbles sinking in vertical oscillating vessel with liquid — «wave» and «non-wave» («oscillating») mechanism. In the first case, the determining significance belongs to wave amplitude gradient, conditioned by bubble surrounding media compressibility, and in the second — to compressibility of bubble itself. The present work generalizes the authors' studies, performed over recent years, dedicated to investigation of this effect. Both proposed mechanisms of sinking are considered simultaneously — motion of gas bubble in oscillating vessel with liquid is studied, taking into account compressibilities of bubble and of gas-saturated surrounding layer that is formed near free surface of liquid through turbulization. Conditions are determined, under which bubble will sink in such compressible medium. An expression is derived for critical thickness of gas-saturated layer of liquid; when this thickness is exceeded, such layer starts expanding down into vessel, i.e., the condition of oscillatory instability of gas—liquid system separate state. It is shown, that bubble sinking condition is essentially affected by both its own compressibility and compressibility of its surrounding medium. An expression is obtained for average velocity of bubble motion in gas-saturated layer of liquid, essentially dependent on bubble sinking depth and oscillation parameters.

keywords Flotation, oscillation, compressible bubble, conditions of sinking, compressible gas-saturated liquid.
References

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