Modelling of aerodynamic separation of grain material in combined centrifugal-pneumatic separator. engineering for rural development.

Abstract

One of the ways to improve the efficiency of post-harvest processing of grain is the preliminary fractionation of the grain mass, that is, the distribution into fractions for food, seed and fodder purposes. The use of airflows at the initial stage of separation ensures the preliminary formation of grain flows with minimal energy consumption and ensures the receipt of grain for various commodity operations. The high correlation of indicators of the technological properties of the components of the grain material allows the use of airflow at various stages of post-harvest processing of the crop. In most constructions of separators, the airflow is used to clean the lightest impurities. In this work, it is proposed, based on the integration of pneumatic separating working bodies, to develop a combined centrifugal and pneumatic gravity separator for separating components from the grain mixture that differ in mass and aerodynamic properties. The technology for separating the components of the grain material consists of preliminary removal of light impurities using a centrifugal-pneumatic method and dividing the grain into fractions using a pneumatic gravity method in an annular channel with an additional outpouring of radial airflow. The parameters of the combined wind separator are determined using additional mathematical models with trajectory analysis, computational fluid dynamics (CFD) methods and experimental verification. The results of experimental studies confirmed the possibility of dividing the grain material into two fractions with a percentage of fractions in the output of 39% to 61%.