Influence of an equal width polygon groove-tooth wheel on feeding performance of the seed feeding device for wheat

This work aimed to investigate the influence of the equal width polygon groove-tooth wheel on both filling and feeding performance to enhance the performance of the seed feeding device of the air-assisted centralized metering device for wheat. This paper conducted an analysis of the equal width polygon groove-tooth wheel formation principles. The EDEM simulation compared and analyzed the influence of the structural types, including equal width triangular, equal width pentagon, equal width heptagon, equal width nonagon, and circular groove-tooth wheel, on seed population disturbance ability, filling, and feeding performance. The simulation results showed that when the rotating speed of the feeding shaft was 20r/min, the average kinetic energy of the seed population decreased gradually, and the ability to disturb the average seed population decreased in turn, but the interval between the adjacent average kinetic energy peaks decreased, and the frequency of disturbed seed population increased with the increase of the number of sides of the equal width polygon groovetooth wheel. The average kinetic energy of the seed population was significantly higher under the disturbance of the equal width triangular, pentagon, heptagon, and nonagon groove-tooth wheels, increasing by 371.32 %, 209.23 %, 91.02 %, and 53.37 %, respectively, compared to that of the circular groove-tooth wheel. Within the feeding shaft rotating speed range of 10 - 60r/min, the average kinetic energy of the seed population gradually increased in the equal width polygon groove-tooth wheel type feeding device gradually with the increase of the feeding shaft rotating speed. Using the quality rate of seed filling (2 +/- 1 seeds/hole) and the missing rate of seed filling (0 seed/hole) as benchmarks, the equal width heptagon groove-tooth wheel exhibited the quality rate of seed filling of 93.98 % and the missing rate of seed filling of 2.78 %. The seed feeding quantity and seed feeding time had high linearity, and the seed filling and seed feeding performance were better. In the range of 10 - 60r/ min for the rotating speed of the equal width polygon groove-tooth wheel, there was a positive correlation observed between the average kinetic energy of the seed population and the increment of the feeding shaft rotating speed. The variation in feeding shaft rotating speed exhibited minimal influence on the feeding performance. The bench test verified the performance of the seed feeding device equipped with the equal width heptagon groove-tooth wheel in terms of both seed feeding and seeding efficiency. The results demonstrated that within the feeding shaft rotating speed range of 10 - 60r/min, the coefficient of variation(CV) for seed feeding rate stability did not exceed 2.14 %. Additionally, the damage rate during the feeding process remained below 0.2 %. These outcomes aligned with the requirements of stable wheat seed feeding.