The influence of solubility on the structure of the cavity bottom during droplet merging in the impact mode


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The multipoint lighting was used to visualize the flow pattern created by a freely falling drop in a fluid at rest. The initial stage of merging a drop of potassium permanganate solution with water, drop of water with a solution of ammonium thiocyanate, and spreading a drop of aniline and crude oil in a pool of water was studied. The main attention was paid to the analysis of the flow pattern near the bottom of the cavity in the impact mode, when the kinetic energy of the drop significantly exceeds its potential surface energy. An "intermediate layer" is formed un-der the bottom of the cavity upon contact of the mixing liquids. This layer is a product of dis-solution of thin fibers of the droplet substance invading the target fluid. Poorly soluble aniline partially pushes through the bottom of the cavity. Crude oil does not penetrate through the sur-face of the liquid at the initial stage of flow in this mode. The values of traditional dimen-sionless parameters that are Reynolds, Froude, Weber, Bond, Ohnesorge numbers, and addi-tional ones that are the ratios of energy components and their densities, as well as relative densities and surface tension coefficients of contacting media values are presented

drop, miscible and immiscible fluids, electrolytes, aniline, petroleum, cavern, intermediate layer

DOI: http://doi.org/10.33257/PhChGD.26.2.1175


Volume 26, issue 2, 2025 year


Влияние растворимости на структуру дна каверны при слиянии капли в импактном режиме

Методом многоточечной подсветки выполнена визуализация картины течения, создаваемого сво-бодно падающей каплей в покоящейся жидкости. Изучен начальный этап слияния капли раствора перманганата калия с водой, капли воды с раствором роданида аммония, а также растекания капли анилина или нефти в бассейне с водой. Основное внимание уделено анализу картины течения около дна каверны в импактном режиме, когда кинетическая энергия капли заметно превышает ее потен-циальную поверхностную энергию. Под дном каверны при контакте смешивающихся жидкостей образуется «промежуточный слой» – продукт растворения тонких волокон вещества капли, втор-гающихся в принимающую жидкость. Слабо растворимый анилин частично продавливает дно ка-верны. Нефть на начальном этапе не проникает сквозь поверхность жидкости в условиях опыта. Проведены значения как традиционных безразмерных параметров – чисел Рейнольдса, Фруда, Ве-бера, Бонда, Онезорге, так и дополнительных – отношений компонентов энергии и их плотностей, а также относительных плотностей и коэффициентов поверхностного натяжения контактирующих сред

капля, смешивающиеся и несмешивающиеся жидкости, электролиты, анилин, нефть, каверна, промежуточный слой

DOI: http://doi.org/10.33257/PhChGD.26.2.1175


Volume 26, issue 2, 2025 year



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