Simulation and Experimental Analysis of the Wind Field inside the Air Deflector of a Sugarcane Leaf Cutting and Returning to Field Machine

摘要

This work investigated the self-excited wind field caused by rotating knife rollers inside the air deflector during the operation of the sugarcane leaf cutting and returning to field machine. Based on the arbitrary Lagrangian-Eulerian (ALE) method, a fluid-structure interaction simulation of wind field inside the air deflector was carried out under the condition of two clockwise rotating knife rollers, exploiting the finite element software LS-DYNA. The simulation results revealed an airflow confluence surface generated during the process of the airflow interaction, accompanied by formation of vortices. The wind field in the left and right outlets of the air deflector and regions near the ground between the two knife rollers is regular and stable. Airflow velocities below the deflector near the ground were measured. With both simulation and experimental evidences, we demonstrate that the horizontal wind velocity decreases with an increasing elevation above the ground, with a simulation deviation of velocity decreasing rate no more than 12%. In contrast, the vertical wind velocity shows an opposite correlation with height, and the simulation deviation of velocity increasing rate is no more than 26%. Our simulation and experimental data indicate a consistent variation trend of wind velocity. Insights from this study can be useful in designing and optimization of relevant structures and mechanisms involving air deflectors and knife rollers.