Study Of The Device For Seedling Mud Lifting And Conveying On Rice Paddy Field

Rice paddy field seedling is one of the important links of rice cultivation.Because of its simple process and low cost of seedling cultivation,it is widely used in southern China.In the mud paving,the mud should be paved into the seedling tray after mixed evenly,removed impurities,lifted and conveyed in the field.At present,the mechanized operation is only part of the process of mud paving,and the mud lifting and conveying process is still used labor-intensive and inefficient manpower.In order to make the rice paddy field seedling adapt to the rapid promotion of transplanting mechanization,reduce labor intensity and improve work efficiency,it is necessary to carry out in-depth study on the mechanization and conveying technology of field seedling mud.Based on the analysis of the current mechanization technology of mud laying,this paper uses EDEM discrete element simulation software to establish the equivalent wet model of mud,and analyzes the flow characteristics of mud.Then,combined with the application of tilting screw conveyor in material lifting and conveying,the whole structure and key components of the machine for mud lifting and conveying are designed,and then the discrete element simulation test of mud lifting and conveying process is carried out.Developed the prototype and made the optimization test to get the best working parameters of the machine,and then realized the integration of the seedling and the transportation.The main contents and conclusions of this paper are as follows:(1)The physical characteristics of seedling mud were analyzed,and model of mud in the EDEM software was corrected by the slump test.Based on the analysis of the fluidity of field seedling mud,the comparison of the results of muddy wet granule model slump test and the actual mud slump test results which was established in EDEM software,the correction of model parameters,the gap between them is 5%.In this paper,it indicated that the mud discrete element model and its evolution law can simulate the fluidity of the actual seedling mud,and finally the parameters of the wet granule model of the seedling mud in the EDEM software were obtain.(2)The field of mud lifting and conveying machine key components was determined and machine with the integration of mud transport and upgrading was designed.According to the requirements of mud lifting and conveying,the transmission system and screwing conveyor mechanism of the machine were designed.The transmission ratio of the transmission system is 21:1;the diameter of the spiral blade is 100mm;the blade pitch is100mm;the inner diameter is 30mm;the length is 1500mm.The influence of the angle of the screw shaft and the speed of the screw shaft on the screwing conveyor performance was obtained.The design of the floating plate depth and the field moving device was also carried out.(3)The working simulation model of spiral mud lifting and conveying device was established and the simulation experiment was carried out,by using EDEM discrete element simulation software.Taking the spiral axis as the research object,the simulation model of the lifting and conveying device was established in the EDEM discrete element simulation software.The wet particle flow law of the mud was obtained by the discrete element simulation results,and the mud dispersion Element wet granule model rationality.The single factor virtual simulation experiment was carried out on the rotation speed of the screw shaft and the angle of the screw shaft.The influence of various factors on the conveying results is as follows:increasing the speed of the screw shaft at the same helical angle increased the mud mass flow of the mud lifting and laying machine,and the power consumption of the device increased with the same speed,the mass flow rate of the particles decreased with the increase of the inclination angle of the screw shaft,and the power consumed decreased with the helix angle of 45~o.(4)The screw-type mud lifting and conveying prototype was developed,and the prototype performance test was carried out.The experiment showed that when the optimized working parameter was 45~oand the screw shaft speed was 250r/min,the lifting performance was improved and the conveying performance was the minimum power consumption.The experimental results show that the mud transport performance was positively correlated with the rotation speed of the screw shaft,and it was negatively correlated with the inclination angle of the screw shaft.The influence of the angle of the screw shaft on the mud transport performance of the device was greater than that of the screw shaft.According to the requirements of field laying mud,the optimal working parameters of spiral type mud lifting and conveying device were obtained by the test results.The screwing shaft angle was 45~oand the speed of the screw shaft was 250r/min.it was proved to have good lifting and conveying performance,and the minimum power consumption.The results showed that the prototype was able to complete the lifting and conveying of field seedling mud,and the productivity was about 600 disk/h.