Analysis and experiment of flow field in sugarcane leaf cutting and returning machine

Abstract

In order to study the characteristics of self-excited wind field caused by the rotation of flexible knife in different working modes of sugarcane leaf cutting and returning machine, a three-dimensional model of sugarcane leaf cutting and returning machine was established. By using the arbitrary Lagrangian Euler method (ALE), the flow field in the body was analyzed under different working conditions (two knife rollers moved clockwise in the same direction –case 1; the main cutter roll anticlockwise and the driven knife roller clockwise –case 2; the main knife roller clockwise and the driven knife roller anticlockwise –case 3). The results showed that: when the cutting roller worked to 0.1 and 0.118 s, four vortices were generated in case 3, and the maximum wind speed reached 68.8 m/s, which was easy to cause flow field disturbance; At a distance of 40 mm from the ground in case 2, the maximum velocity in Y direction generated in the area between the two rollers was 51.1 m/s, and that was the most. The high speed was 22.8 m/s in case 1, then the difference between them was 28.3 m/s; the working mode of case1 was more conducive to reduce the problem of winding the body caused by the blowing of sugarcane leaves. In order to verify the accuracy of the simulation results, wind speed test and high-speed photography test were carried out. The maximum difference between the test and the simulation structure was The difference between the simulation value and the test value is 0.5 m/s, which was caused by the interference of the anemometer on the flow field when the anemometer was placed in the body, which was within the acceptable range, so the model is more accurate and the simulation structure is reliable. This study also provided a reference for the further optimization of the flow field in the sugarcane leaf returning machine.