Modeling the loading process of pneumatic separation channels

The object of research is the problem of uniform distribution of bulk materials across the width of the working elements of the separation equipment. Such a problem limits the productivity and quality of the process of separation of bulk materials by aerodynamic and dimensional characteristics. To ensure uniformity of the layer of bulk material across the width, an integrated design of the loading device is proposed, which consists of a gable surface with a variable angle of inclination from the center of the feed to the extreme limits of the device. The working part of the device is made in the form of surfaces of variable width, and the width of each slope of the surface increases proportionally to the distance to the walls of the housing. This allows for controlled distribution of the material across the width. The studies were conducted using analytical and experimental methods. To determine the parameters of the movement of the bulk grain medium along the integrated inclined surface, analytical expressions were obtained that take into account the parameters of the proposed loading device and the properties of the bulk grain material. The patterns of change in the rate of descent of particles of bulk grain material from the inclined surface, as well as the dependence of the velocity of their fall to the hopper bottom, were obtained. Experimental studies were based on high-velocity video recording of the process with identification of dynamic parameters of bulk material and comparison with modeling data. The adequacy of the model was confirmed by experiments with a difference of up to 3.6 %. The influence of the following significant factors on the final velocity of particles of bulk grain material (BGM) was established: the length of the sloping surface at the level of 47.5–116.5 %, then the distance from the surface to the hopper bottom at the level of 76.7–85.6 % and the angle of inclination of the sloping surface at the level of 24.4–41.1 %. The ranges of variation of the BGM particle velocities were established: the initial velocity of particles on the sloping surface 0.82–1.27 m/s, the velocity of particles descending from the sloping surface 0.85–1.43 m/s, the velocity of falling particles 0.68–1.47 m/s. The research results were rational parameters of the integrated loading device, which provides excellent particle movement velocities and leads to uniform distribution of bulk grain material across the width of the separation equipment with an inlet to outlet ratio of (1:5). The results obtained prove the existence and method of scientific and technical solution to the problem, create conditions for further research and design of separation equipment with high technological indicators.