Development And Experiment Research Of Oblique Submerged Reverse Deep Rotary Cultivator

With the development of agriculture,the rational use of a large number of straws produced by agricultural production is an important problem facing the development of ecological agriculture in China.Straw returning to field can not only solve the problems caused by the incineration,but also improve the soil quality,improve the soil fertility and reduce the amount of fertilizer.In view of the current demand for agricultural production and the problems existing in farming machinery,this paper presented a method of oblique submerged reverse rotary tillage,which not only has good performance of plough stubble,but also has good performance of deep tillage.In this paper,the mechanization of oblique submerged reverse rotary tillage was studied,and the soil throwing was emphatically analyzed and studied by the method of combining computer modeling with finite element analysis.Furthermore,the oblique submerged reverse rotary cultivator was designed on the basis of the above research and the related field experiments were carried out.In this paper,the motion equations and trajectories of the rotary blades,as well as the velocity and acceleration of the rotary blades were obtained by the kinematics analysis when the oblique submerged reverse rotary cultivator was working.According to the law of motion,the pitch of the soil cutting and the projection height of furrow bottom at the oblique submerged reverse rotary tillage were studied by theoretical analysis.The results show that the pitch of the soil cutting is related to the forward velocity of the machine,the speed of revolution of the cutter shaft and the angle of the cutter roll,and the projection height of furrow bottom is related to the rotary radius of rotary blade,the number of rotary blade,the forward velocity of the machine,the speed of revolution of the cutter shaft and the angle of the cutter roll.Moreover,the existence of the oblique angle can reduce the pitch of the soil cutting relatively and the increase of the angle of the cutter roll can increase the projection height of furrow bottom and reduce the quality of the tillage.Therefore,the theoretical analysis shows that the oblique submerged reverse rotary tillage has a better property of soil crushing and soil throwing.In order to further study on the performance of throwing soil of oblique submerged reverse rotary tillage,the virtual simulation model of oblique reverse rotary tillage was established by the finite element software ANSYS/LS-DYNA and SPH algorithm and the corresponding oblique rotary tillage test bench was designed to verify the reliability of the simulation model in this paper.Moreover,repeated sampling orthogonal virtual tests of throwing soil of oblique rotary tillage were made with oblique angle,forward speed,depth of submerged and the speed of revolution of cutter roller as the four factor test,and three levels for each factor,and back-throwing-soil rate as test indexes by the simulation model has been verified well and orthogonal design method.The test results were analyzed through intuitive analysis,variance analysis and regression analysis in proper sequence and the results show the order of main factors affecting the back-throwing-soil rate,the importance of each factor on the test results and the relationship between the significant factors and the back-throwing-soil rate.In order to understand the actual tillage performance of the oblique submerged reverse deep rotary cultivator,the basic structure and working principle of the oblique submerged reverse deep rotary cultivator were emphatically introduced which including the calculation of the oblique angle,the design of the corresponding suspension bracket and the structure and working principle of the components such as the rotary tillage cutter roller,the weed control device and the leveling device.Besides,in order to study the influence of tool roll skew on the balance of the machine tools,the lateral force of the designed machinery was analyzed by ADMAS software.The analysis results showed that the equipment can be balanced by squeezing the side soil,and it will not affect the normal use of the machine tools.Moreover,the prototype of the oblique submerged reverse deep rotary cultivator was manufactured and field experiments were carried out under the condition of stubble and no stubble,respectively.The test results show that the equipment can not only break soil and bury stubble at a time,but also realize deep rotary tilling using short rotary tilling blades by measuring of tillage depth,stability of tillage depth,soil-breaking rate and residue covering rate.Therefore,the oblique submerged reverse deep rotary cultivator can meet the requirements of the national standard and deep tillage.The results of this paper provide a theoretical basis for the design of deep rotary tillage in the future.