横轴流联合收获机脱分选装置创新设计与性能试验

Abstract

Aiming at the problems of high grain entrainment loss rate and impurity rate of traditional horizontal axial-flow combine harvesters, a horizontal axial-flow threshing-separating device with coaxial differential threshing drum, conical cleaning fan, double-layer vibrating screen and spiral plate-tooth re-thresher is designed. Meanwhile, a test-bed with a feeding rate of 2 kg/s is designed to improve the device performance. The test through quadratic orthogonal rotation combination design method is used to inspect the effects of the differential drumspeed combination, conical fan blade taper, and length ratio of the high and low speed sections of the differential drum on the loss rate, crushing rate , impurity rate and threshing power consumption. The regression mathematical models of the loss rate, crushing rate, impurity content and threshing power consumption are established, and the multi-objective optimization calculation of the regression mathematical model is carried out by using MATLAB optimization toolbox. The results show that the order of the three factors affecting the loss rate and impurity content of the horizontal axial-flow threshing-separating device is the differential drumspeed combination, the conical fan bladetaper, and the length ratio of high and low speed sections of the differential drum. The field test results show that the performance index of the horizontal axial-flow separation device is better than the requirements of the national standard.