SIMULATION OF SOYBEAN SEED PHYSICAL PROPERTIES ON FILLING PERFORMANCE

Soybean seed physical properties is important on filling performance during planting. To evaluate the effect of sphericity and variation coefficient of mean diameter on seeding performance in seed metering device, seven soybean genotypes [The Ken Dou 40, Ken Feng 17, Qing Ren Black Soybean, Black Soybean, Hei He 44, Bei Jiang 91 and Dong Nong 52] were tested to measure the length, width, thickness, and calculate these sphericities, mean diameter and variation coefficient of mean diameter, respectively. The model of soybean seed with equal mean diameter was developed and the discrete element method was used to set the different sphericity and variation coefficient of mean diameter. A simulation study was performed in the model of the cell wheel feed followed by mathematical modeling of the experimental data, and the data with response to the surface methodology was analyzed. Results showed that while the sphericity had a significant effect on both single- and empty -seed rates, the variation coefficient of mean diameter had a significant effect on the multi -seed rate. With the increase of sphericity, the single-seed rate increases but empty-seed rate decreases. With the increase of variation coefficient of mean diameter, the multi-seed rate increases. Based on our results, the Ken Feng17, Ken Dou 40, Black Soybean and Qing Ren Black soybeans were only selected for bench test. The relative error between the experimental results and the theoretical values of the regression analysis was small; however, the respond trend of factor index was same. Our study suggested that the effect of sphericity and variation coefficient of mean diameter on seeding performance can be used by using simulation experiment.