RATIONALE FOR THE SELECTION OF THE MATHEMATICAL MODEL FOR DESCRIPTION OF HYDRODYNAMICS OF APPARATUSS WITH A WEIGHED TRANSPORTABLE LAYER BY MEANS OF COMPUTING HYDRODYNAMICS
Apparatuss with a weighed transportable layer (AVTS) refer to a new perspective equipment for drying dispersed materials in multi-tonnage chemical and mining chemical plants. They operate in an active hydrodynamic regime at fictitious gas velocities approaching the velocity of the average particle diameter of a polydisperse material. The hydrodynamic regime used in AVTS occupies an intermediate position between the well-studied processes of fluidization and pneumatic transport, but differs markedly from them and is comparatively little studied. At present, promising is the use of computer fluid dynamics (CFD) tools to obtain preliminary data necessary for developing the design of an experimental setup, determining the boundaries of the study of the hydrodynamic regime in AVTs. In this regard, it is relevant to consider the main approaches to modeling the motion of two-phase flows (gas-solid) in the suspended layer, the rationale and choice of a mathematical model for calculating apparatus with a weighed transportable layer. In this paper, we consider the classification of "simulation" models depending on the place of application and the description of the phase interaction, analysis of the advantages and disadvantages of the main analytical models, substantiate the choice of the basic model for description of hydrodynamics in AVTS, select the software product ANSYS CFX, CFD code. Taking into account the peculiarities of using ANSYS CFX with the application of "Eulerian-Eulerian multiphase flow" and "Particle Transport Modeling" models, the description of hydrodynamics of AVTS was performed. The obtained results confirm the AVTS operation in the given process conditions and the geometric dimensions of the apparatus.