Математическая модель гидродинамики движения двухфазного восходящего потока в пневмоклассификаторах переменного сечения

Abstract

Classification processes involve division of granular materials into two and more fractions according to the particles size. Notably, impurity content in these products is acceptable in small amounts. The high separation level during the particulates classification processes affects not only the raw materials unit consumption and its quality but also has an impact on the productivity and efficiency of other machines and apparatus in the flowsheet and, eventually, on the technical-and-economic indicators of the production in general. This paper deals with the developing the hydrodymamics mathematical model of two phase flow motion. To reach the set goal, the authors created the mathematical model of one phase flow (gas phase). The next stage was the creation of the mathematical model of two phase flow, as exemplified by the gas phase and the solid particle. This model is unique due to the fixation of the dependence of solid particles velocity on the apparatus body and the gas flow profile. The authors worked out the equations to define the velocity of the gas flow and the velocity of the solid particle at every point of the variable cross-section apparatus body. The authors developed the characteristic curve of gasflow line in the pneumatic classifier body. The solid particle trajectories were defined in the body of the pneumatic classifier with variable cross-section. The velocity distribution and the influence of the gas flow on the individual solid particle are deeply analyzed in the paper. The conclusions also deal with the trajectory change of the individual particle within the apparatus body.