Design And Experiment Of The Electrical Drive Side Deep Hill-drop Fertilization Device For Precision Rice Hill-direct-seeding Machine

Rice is a kind of major food crop in China,fertilizer application has become an indispensable step in the growth process.Side deep hill-drop fertilization can fully utilize fertilizer efficacy,greatly reduce the loss of fertilizer.Thus,the use amount of fertilizer can be reduced,meanwhile it is benefit for rice growth,rice yield increasing,and environment pollution reducing.In this paper,on the basis of reviewing and analyzing the development curent status of paddy field fertilization machine at home and abroad,surface and full-layer fertilization were always adopted in rice direct-seeding process.Side deep hill-drop fertilization in the precision rice hill-direct-seeding was utilized,an electrical drive outer slot wheel fertilizer applicator with the slot being filled by fertilizer,brush clearing,being guided by the guiding plate and hill-drop fertilization.Based on the fertilizer applicator,the electrical drive side deep hill-drop fertilization device for precision rice hill-direct-seeding machine was designed for meeting the demands.Through theory analysis,structure design,computer simulation,bench test and field experiment.The research work has been carried out,and main research contents are as follows:(1)Physical and mechanical property test of fertilizer particlesSelected suitable mixed fertilizers for rice direct-seeding in Heilongjiang province as the research object,the fertilizer mainly includes urea,superphosphate and potassium nitrate.The fertilizer particle density,size,equivalent diameter distribution,spherical rate,moisture content rate,static and sliding friction coefficient,reposing angle and collision restitution coefficient were measured by the physical and mechanical properties test,providing the parameter foundation for structure design and simulation analysis of fertilizer applicator.(2)Structure design of electrical drive outer slot wheel fertilizer applicatorBased on the methods of the slot being filled by fertilizer,fertilizer-clearing of brush,fertilizer-guiding of guiding plate and hill-drop fertilization,an electrical drive outer slot wheel fertilizer applicator that satisfies the fertilization requirements of rice hill-direct-seeding with simultaneous hill-drop fertilization was developed.Through theory analysis of the filling stage,structure parameters of outer slot wheel were determined,and through the kinematics and dynamics analysis in the process of fertilizer-guiding,the length and installation angle of fertilizer-guiding plate were determined,and designed other key mechanical parts,such as blocking wheel,adjusting sleeve,fertilizer shell and fertilizer case,and electric parts were selected,then connected mechanical parts with electric parts,and circuit of fertilization device and working process of field fertilization circuit were designed.(3)Simulation analysis of electrical drive outer slot wheel fertilizer applicator based on discrete element methodTaking the fertilizer applicator as the research carrier,then the model of fertilizer applicator constructed in CATIA was imported into the discrete element software EDEM,and constructed spherical particle models of urea,superphosphate and potassium nitrate.By the way of simulation and analysis,got the fitting line and relationship equation,which reflected the influence of working rotation speed and opening length of outer slot wheel on the fertilizing amount per revolution,and laid the foundation for the subsequent bench test and field experiment.(4)Performance bench test of electrical drive outer slot wheel fertilizer applicatorWith the help of the JPS-12 computer vision precision metering device performance test bench,the performance test bench for fertilizer applicator was set up.First,the fertilizing working rotation speed and the opening length of outer slot wheel were taken as factors,and the fertilizing amount per hill was taken as index.Through data processing analysis of EXCEL software,obtained changing rules between two factors and fertilizing amount per hill,and combined influence rules between two factors and fertilizing amount per revolution.The fertilizing stability variation coefficient of fertilizer applicator was analyzed.The influence of factors on fertilizing amount per revolution was studied,comparing with that of the simulation test,which verified the feasibility of virtual simulation test.(5)Configuration design and field experiment of electrical drive side deep hill-drop fertilization device for precision rice hill-direct-seeding machineAccording to the agronomic requirements of side deep hill-drop fertilization in the process of precision rice hill-direct-seeding,the profiling mechanism and fertilizer furrow opener were designed for completing the configuration of side deep hill-drop fertilization device.Mixed fertilizer was used,the experiment was conducted under the selected condition.The result shows that the average qualification rate,re-fertilizing rate and leak-fertilizing rate of fertilizing amount per hill were 87.49%,5.95% and 6.56%;The average fertilizing hill spacing ranged from 145 to 154 mm and variation coefficient ranged from 12.1 to 18.9%.The average fertilizing depth ranged from 49 to 52 mm and variation coefficient ranged from 5.8 to 8.3%.The average distance between rice seed and fertilizer ranged from 29 to 31 mm and variation coefficient ranged from 5.1 to 8.5%,which can meet the agronomic requirements.