Experimental Study On Performance Of Pneumatic Seeding System

To research the performances of pneumatic seeding system, a test stand about the pneumatic seeding system was developed. In this study, the tests were performed based on the quadratic general rotary unitized design, the seed application rate and the air flow rate were selected as affecting factors, the variability coefficient of evenness of feeding rate between rows and the variability coefficient of seeding stability of sum rows were assigned as the test indexes. To establish mathematical models and optimize parameters, SAS9.1and Matlab7.0software were employed for data analysis. To further study the performances of dimpled tube, contrast tests were performed to compare the performances of dimpled tube and smooth tube.The main conclusions and results from the study are as follows:(1) A test stand about the pneumatic seeding system was developed. It is suitable for several kinds of pneumatic seeding systems and seeding performances test.(2) The regression models and the optimization mathematical model between factors and indexes were established, it can match the seed application rate and the air flow rate according to the different requests of seed application rate, and it will provide guidance for practical application combined with economic requirements.(3) The optimum parameters were combined:the seed application rate was297.26kg/hm2, the air flow rate was7.99m3/min, and the theoretical indexes were estimated:the variability coefficient of evenness of feeding rate between rows was0.630%, the variability coefficient of seeding stability of sum rows was0.260%. The verification test showed that the models were suitable to effectively forecast factors and indexes, and could provide reference for the study of pneumatic seed metering system and the practice application.(4) Contrast tests of dimpled tube and smooth tube showed that the dimpled tube had better performances than smooth tube.