Abstract
Due to the fact that the airflow field cannot solve the accumulations of mixtures on the vibrating screen surface, a conical fan was designed. The CFdesign software was used to numerically simulate the airflow field of the cleaning room. The results showed that compared with the cylindrical fan, the mass of threshed mixture in the main falling area of the vibrating screen surface under the conical fan accounted for 65.4 %. The accumulation central point of the threshed mixture deviated 165 mm from the vibrating screen width to the grass discharge outlet. Under the conical fan, the impurity content of the mixture not screened was 6.8 %, and the cleaning loss rate was 0.2 %.