Numerical simulation and experimental verification of mulch spreading system of paddy field based on CFD

Abstract

In order to realize the technology of mechanized mulching planting in paddy field, the flow of surface soil in paddy field was simulated by using Fluent software, and the flow of air and mud during parallel slide of equipment in two-phase fluid medium of air and mud was studied. The simulation method of the two-phase flow was determined, and the two-phase diagram of air and mud and velocity and pressure diagrams of fluid around the model were obtained. The mud around the model was divided into four regions Mq, Mc, Mx, Ms. Based on this, the structural parameters of the mulching system were optimized. At the speed of 1.65 m / s and the viscous coefficient of 2.72kg/m• s, Fluent was used in simulation analysis and experimental verification of the four models of soil-engaging equipment in the optimized paddy field mulching system. The results show that: the increase of α, β (vertical inclination angle α = 150 ° and end embedded angle β = 150 °) can significantly improve the traction resistance and mud obstruction of the equipment. The relative error of the traction resistance of four models of cylindrical roller, elliptical roller, ejector plate and ship plate was 8.3%, 10.27%, 6.67% and 13.74% respectively. The simulation results are in good agreement with the experimental data, which verifies the reliability of the model and provides a new research method for the study on surface soil of paddy field.