Discrete Element Parameter Calibration for Red Soil with Different Moisture Contents in Fujian Tobacco-growing Areas
This paper aims to establish a discrete element parameter model of red soil with different moisture contents,and explore the calibration methods suitable for red soil with different moisture contents.Firstly,the physical experiments of red soil with different moisture contents were carried out by using the cylinder lifting method,the repose angle were measured and the regression equation of moisture content and repose angle was established.Secondly,the EDEM discrete element software was used to simulate the repose angle of red soil with different moisture contents.Then,taking the repose angle as the response value,the Plackett-Burman experiment was used to screen out 3 significant factors from 10,and the optimal ranges of the significant factors was determined by the steepest ascent experiment.Finally,the Box-Behnken experiment was used to establish the quadratic regression model of repose angle and significant factors,and the relationship model of moisture content and discrete element parameters was obtained.In order to verify the validity of the model,comparative analysis was carried out using the Lang method experiment.The model of moisture content-repose angle of red soil in the range of 10%-35%was established,and the correlation coefficient of the model was 0.992.The significant factors and their optimal ranges are:red soil shear modulus of 4.6-8.2 MPa,red soil-red soil static friction coefficient of 0.52-0.84,dynamic friction coefficient of 0.13-0.29.The P-value of the relationship model of repose angle and discrete element parameters of red soil is 0.002,and the relative error of repose angle between simulation experiment and physical experiment is not more than 2.13%.The relationship model of moisture content and discrete element parameters was verified by experiment,and the relative error between the simulation experiment and the physical experiment results was not more than 4.25%,indicating that the model is consistent with the actual situation,and the discrete element parameters calibrated by the model are reliable and effective,which can provide theoretical support for the research and development and simulation optimization of tobacco machinery under the red soil geological conditions in Fujian tobacco area.
red soilmoisture contentdiscrete elementrepose angle
万方数据
维普
