Analysis of Influencing Factors and Operation Quality Evaluation Strategy of Straw Crushing and Scattering System

Abstract

First, through a single factor test, it was determined that the conveying and feeding speed range was 0.9~1.5 m/s, the rotating speed range of straw chopper shaft was 1900~2300 r/min, and the moisture content of straw was 26~34%. Then the Box–Behnken experimental design method was adopted, with conveying and feeding speed, cutter shaft rotation speed, and straw moisture content as influencing factors; small and stable specific power consumption and maximum coverage uniformity are taken as evaluation indexes. The influence rules of various factors on operation indexes were analyzed, and response surface analysis was carried out. Further, the optimization function in Design-Expert12.0 was used to determine the optimal parameter combination as follows: Conveying and feeding speed of 0.8 m/s, rotating speed of cutter shaft of 2059.9 r/min, moisture content of straw of 30.7%, corresponding specific power consumption and coverage uniformity of 1163 J/s2 and 99.1%, respectively. Finally, the seeding system was mounted behind the straw crushing and scattering system for a field verification test. The results showed that when the crushing and scattering system of the whole machine operates with the design parameters, the specific power consumption was 1260 J/s2, the uniformity of straw coverage was 94.7%, and the error with the experimental value was less than 5%. The effect was better than the standard requirement. The test realized the crushing and uniform coverage of high-quality straw residues after rice harvest, which proved the scientific and reliable test-bed of the crushing and scattering system.