This article examines the study of the dimensional characteristics and aerodynamic properties of soy grains and straw impurities, which is important for optimizing the purification processes at harvesters. It has been established that soy plants and grain differ significantly from colossal crops, which necessitates a deeper study of the technological properties of small soy pile coming for purification. It is shown that for effective separation of these components by air purification, it is important to take into account the size and sailability of the particles of the mixture. The dimensional characteristics of the whole and crushed soybean grain, as well as straw impurities, are presented in the form of variation curves demonstrating the stability of these features. As a result of studies, it is determined that the straw impurities have a critical speed of 2–8 m/s, which makes it difficult to separate them from soy grain, since these parameters overlap. At the same time, it is proposed to use the difference in critical speeds between whole and crushed soybean grain for double-threaded processing of combine harvesters, which allows to significantly increasing the separation efficiency, releasing up to 95% of crushed grain and completely removing straw impurities. Aerodynamic studies using the example of the first seed fractional flow showed that the inclined air flow generated by the combine fan can effectively separate from the seed fraction more than 66% of crushed grain and 84% of straw impurities. The results of this study contribute to improving the quality of seeds and the efficiency of soybean harvesting processes.
I.М. Prisyazhnaya (Wed,) studied this question.