Influence Research Of Subsoiling In Tandem On Soil Disturbance

The subsoiling in tandem can promote the soil maturation in the deep soil layer,and reduce the blocking phenomenon of crop stubble and weed,which has a good development foreground.In this paper,with the basis of the theoretical analysis of subsoiling in tandem,the digital soil-bin experiment method was used to study the influence that the depth of the front subsoiler,the front subsoiler tines and the rake angles of front subsoiler on the soil disturbance of the subsoiling in tandem.The main research contents and conclusions of this paper are as follows.(1)The theoretical analysis of subsoiling in tandem.The soil shear failure and crushing process under subsoiling in tandem conditions was analyzed,and the interaction relationship between subsoiler in tandem and soil was deeply studied fromthe prediction model of soil disturbance volume.The main factors influencing soil disturbance of subsoiling in tandem were the depth of front subsoiler,the width/shape of front subsoiler tine,the rake angle of front subsoiler and the distance between front subsoiler and rear subsoiler.(2)The influence of the depth of front subsoiler on the soil disturbance of subsoiling in tandem.With the evaluation index of soil disturbance effectiveness,the digital soil-bin experiment method was used to study the influence difference of subsoiling in tandem under thedepth of front subsoiler 100,150,200,250 mm.EDEM simulation results showed that compared with single subsoiler,subsoiling in tandem could separate and loosen the soil of different soil layers,reduce the mixture of soil of different soil layers;With the increasing depth of front subsoiler,the soil disturbance range showed a decreasing trend.The soil-bin experiment indicated that after subsoiling in tandem,the width of the soil profile and soil volume expansivity increased with the increasement of depth of the front subsoiler.The soil disturbance coefficient and the stability coefficient of subsoiling depth was the largest when the depth of the front subsoiler was 150 mm.The width of subsoiling furrow,width of soil ridge and soil disturbance coefficient of subsoiler in tandem was bigger than that of single subsoiler,soil roughness and the stability coefficient of subsoiling depth of subsoiler in tandem was bigger than that of single subsoiler,and the height of soil ridge of subsoiler in tandem was small than that of single subsoiler.(3)The influence of the front subsoiler tines on the soil disturbance of subsoiling in tandem.With the chisel tine,arrow tine and sweep tine as objects,the influence of the front subsoiler tines on the soil disturbance of subsoiling in tandemwas studied.Results showed that with the sweep tine as front subsoiler,the subsoiler in tandem had the biggest width of the soil profile,width of subsoiling furrow,the width of soil ridge,soil volume expansivity,soil disturbance coefficient,and the best soil roughness and the stability coefficientof subsoiling depth,the arrow tine took a second place,and the chisel tine was the least.With different front subsoiler tines,the subsoiler in tandem had the bigger width of soil ridge,better soil roughness and stability coefficient of subsoiling depth than single tine,while the subsoiler in tandem had the smaller width of the soil profile and the height of soil ridge than that of single subsoiler.(4)The influence of the rake angle of the front subsoiler on the soil disturbance of subsoiling in tandem.The digital soil-bin experiment method was used to study the influence of subsoiling in tandem under therake angle of front subsoiler 15°,19°,23°,27°,31°.The experiment results indicated that with the increase of the rake angle of the front subsoiler,the width of the soil profile of subsoiler in tandem reduced gradually.When the rake angle of the front subsoiler is 15°,the subsoiler in tandem had the biggest soil volume expansivity and the highest soil ridge.With 27° rake angle of front subsoiler,the subsoiler in tandem got the biggest soil disturbance coefficient.With 31° rake angle of front subsoiler,the subsoiler in tandem got the biggest width of soil ridge,and got the best soil roughness and stability coefficient of subsoiling depth.The width of the soil profile of subsoiler in tandem with different rake angles of front subsoilerwas smaller than that of single subsoiler.