The article presents the results of a study of a high-performance grain cleaning machine for the preliminary cleaning of grain pile with a closed aspiration system. The fl ow regimes of the "air-grain pile" mixture determined by the Reynolds number and the bulk concentration of particles are established. As a result of the modeling, further directions for improving pneumatic systems of grain cleaning machines were determined: the cleaning effi ciency of the Е 0 fraction of pure grain from light impurities, shriveled and crushed grain reaches 82%, the output cleanliness of the grain was 93.7%, and the loss of full grain to waste P z = 0,017%. The average speed of the air fl ow in the separating channel is U = 7.12 m/s, its coeffi cient of variation across the width of the separating channel is v = 12,7%. The results of the experimental data confi rmed the adequacy of using mathematical modeling of the air fl ow in the pneumatic system of a grain cleaning machine to substantiate the basic parameters of the pneumatic system.
The purpose of this work is a mathematical description of sieve frame structural and technological parameters necessary for the implementation of the technological process model of a grain cleaning machine operation. The paper presents the results of the study of the grain cleaning machine sieve frame operation. A kinematic study of a flat swivel multi-link mechanism of the grain cleaning machine sieve frame was made. The method of determining the coordinates of the sieve frame nodal points was developed to calculate their speed. Structural and technological parameters of the mechanism were also studied.