| Fertilization is an important link in the production of the forest and fruit industry,Fertilization must open a deep ditch to ensure continued fertilizer efficiency.Research team has designed 1K-50 ditching machine,there were problems such as high power consumption for trenching,poor stability of tillage depth,and severe vibration during deep ploughing operations,which could not meet the agronomic requirements of trenching in forest orchards.The force system of the soil on the rotary tiller blade roller is complex,and changes with the angle of rotation of the blade roller.In order to simplify the research,the compound reaction force can be decomposed into horizontal resistance and vertical resistance.The horizontal resistance,which is the traction resistance,is the main factor affecting the power consumption of the implement.The vertical resistance affects the vibration and blade wear of the machine body.Based on the research results,this paper used theoretical analysis,soil tank test and discrete element simulation to analyzed the knife roller speed,tool advance speed,the depth of the trench to trench power consumption,horizontal resistance and vertical resistance.It provided data reference for the research of power consumption analysis,blade wear and body vibration of submerged reverse trencher.The main research contents and conclusions are as follows:(1)Analyzed the force situation during the cutting process of the counter-rotating grooved blade,established the working parameters of the tool(blade roller speed,advancing speed,groove depth),knife roller structural parameters(blade roller radius,number of blades,etc.),Blade technical parameters(blade width,cutting edge length,installation angle,cutting angle,etc.)and soil mechanical properties(soil density,cutting resistance coefficient,soil pressure resistance coefficient,soil adhesion coefficient)and mathematical model of trenching power consumption.(2)Through the soil tank test,the actual operating power consumption of the knife roller under certain soil conditions was obtained,which provided a data basis for the calibration of the simulation model and ditch power consumption mathematical model parameters.(3)Used a numerical solution method to calibrate the undetermined coefficients in the mathematical model of trench power consumption.Verification tests showed that the average relative error of the trench power consumption is 11.17%.(4)Used the EDEM 2018 software to establish a soil-knife-roller interaction model suitable for the vineyard soil environment in the south,used trenching power consumption,horizontal resistance and vertical resistance as the test indicators,selected two sets of working conditions with different trenching depths for the simulation test,and obtained the dynamic curve of the test indicators.Compared with the results of the soil trough test,the relative errors of the trench power consumption in the simulation test were 7.27% and 9.36%,respectively,which proved the accuracy of the model.(5)Used the rotation speed of the knife roller,the forward speed and the depth of the trench as the test factors,and the power consumption of the trench,the resistance in the horizontal direction and the resistance in the vertical direction as the evaluation indicators,and used the EDEM model for the test.The results have shown that the significant order of power consumption for trenching is from large to small in order of trenching depth,knife roller speed and advancing speed;the order of significance of horizontal resistance is from large to small in order of advancing speed,trenching depth and Knife roller speed;the order of significance of the vertical resistance from large to small is the depth of the ditch,the advancing speed and the knife roller speed.The interaction between speed and forward speed had a significant effect on vertical resistance.(6)Conducted regression analysis on the results of orthogonal experiments and obtained regression equations of various factors on the evaluation index.Used the dimension reduction method to analyze the influence of single factors on the power consumption,horizontal resistance,and vertical resistance of the trench.The results show that with the increase of the depth of the trench,the average value of the power consumption,horizontal resistance,and vertical resistance of the trench increase steadily.However,when the depth of the trench is greater than 0.42 m,the horizontal resistance showed a slight downward trend.The rotation speed of the knife roll is negatively related to both the horizontal resistance and the vertical resistance.Therefore,in actual production operations,the rotation speed of the knife roll can be appropriately increased to increase the throwing distance of the implement.(7)The best combination of parameters for trenching power consumption obtained by regression model was: knife roller speed 132 r/min,advancing speed 0.06 m/s,trench depth0.3 m,and predicted power consumption 3.89 k W.The verification test shows that the software prediction error is 6%. |
