A MODEL TO DETERMINE THE TRAJECTORY OF SOIL MOTION ON A MOLDBOARD PLOW SURFACE

A mathematical model was developed to determine the soil trajectory of motion on the moldboard plow surface. With the use of the model, trajectory lines of soil particle travel were calculated based on the shape of the moldboard plow surface. Also, with the use of the values of soil properties, soil-metal coefficient of friction, the travel speed of plow and the soil modulus of elasticity, equations of forces were solved for equilibrium condition of the furrow slice passing over the moldboard surface. The use of the model can be extended to the approximation of the soil reaction forces occurring during the plowing operation. Laboratory experiments were conducted to verify the validity of the model. The moldboard shape factors used were derived from the coordinates of points describing the contours of the plow surface as measured by a profilograph.