Дата публикации статьи в журнале: 8.08.2019

Название журнала: Американский Научный Журнал, Выпуск: № (27) / 2019, Том: 1, Страницы в выпуске: 42-45

Автор:
Yaroslavl, Yaroslavl State Pedagogical University by K.D. Ushinsky, Doct. Sc. Techn.

Автор: Koleskin Vladimir Nikolaevich
Yaroslavl, Yaroslavl State Pedagogical University by K.D. Ushinsky, Cand. Sc. Techn

Автор: Lukyanova Antonina Vladimirovna
Yaroslavl, Yaroslavl State Pedagogical University by K.D. Ushinsky, Cand. Sc. Phys.-Math

Анотация: Abstract. Attempts of strict mathematical modeling heterogeneous media that are made in some investigations are necessarily limited by some prior specified theoretical schemes and this fact requires many experimental data for a practical realization. The analysis of known works shows that a physical essence of processes arising at a liquid or gas motion in contact units is insufficiently studied. In articles dealt with a mechanics of disperse systems, issues of constructing computational and theoretical models of concrete industrial devices that would took into account basic experimental facts and sufficiently simple from engineer’s point of view are poorly reflected. The experience of an operation of chemical reactors shows that technical and economic indicators of an industrial process are as a rule lower than evaluated values that were obtained during a design step. Now it can be considered proven that one of the reasons that affects a reactor capacity is heterogeneity of a reagent flow in a granular catalyst layer. In some works [1], [2], [3], [4] computational and theoretical models of a filtration mode of a liquid and gas flow in the still granular layer that is in a stress-strain state under a load from the carrier phase were proposed. Results calculated according these models are in a qualitative agreement with experimental data and a large-scale heterogeneity of a velocity profile corresponds to a scale of granular layer structure heterogeneity. But using Darcy’s law or Ergun’s equation to describe a motion of the carrier phase in an inhomogeneous granular medium requires a justification because a formation of boundary layersis possible along borders of the areas with a different permeability. In radial units with the still granular layer (SGL) it is considered that the large-scale heterogeneity of a radial component of the velocity in the granular layer is caused mostly by reagent flow features in distributing and collecting manifolds. So a majority of works dealt with such units investigates a flow with a suction or injection in channels with perforated walls. A distribution along a distributing manifold length of a cross-section average value of an axial component of the velocity flow was determined by Meshcherskiy’s equation, an energy approach, models of potential flows in [5], [6], [7] an so on. The main task was to provide the stable radial velocity at entering the granular layer. From the above review a conclusion can be made that physical features of the liquid and gas motion in SGL are poorly explored both theoretically and experimentally. For example, conflicting results of measuring the velocity profile in axial units with SGL, a variety of motion equations used for calculation, a lack of information about a volume structure of the granular layer that arises during loading the unit and so on testify it. So there is a necessity to construct computational and theoretical models of concrete industrial units that would took into account basic properties of a technological process and were sufficiently simple engineer’s solutions for designing new technological systems

Ключевые слова: chemical reactor  steam-raw mixture  reagent  large-scale heterogeneity  catalyst  perforated channel  manifold  working area  velocity field  velocity field  

DOI:

Данные для цитирования: Shtern Pavel Gennag’evich Koleskin Vladimir Nikolaevich Lukyanova Antonina Vladimirovna. THE NUMERICAL MODELING OF A FLOW IN PLANE AND RADIAL CONTACT UNITS WITH A STILL GRANULAR LAYER. Американский Научный Журнал. Химические науки. 8.08.2019; № (27) / 2019(1):42-45.

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