Research And Parameters Optimization On New Type Threshing And Separating Device Of Rice

This dissertation presents the operating principle of typical threshing and separating system. And comparative experimental investigations are done between different threshing and separating systems, such as axial-flow-short-rasp-bar-plate-tooth drum with grid concave and spike-tooth drum with grid concave.In this paper, firstly, the rice's configuration parameters, agricultural characteristics are measured. And based on the characteristics of rice and the developmental situation of combine in our country at the present time, we choose two kinds of threshing and separating system mentioned previously as subjects investigated and carry out experimental investigations on the self-designed test device. Through experiments we get the regularities of distribution of outlier along cylinder's axial direction, grain losses, the proportion of different length of threshing residue and power consumption of the two devices, and make a comparison with them between the different systems. Furthermore, by means of regression analysis, applying DPS software, established the mathematical models of threshing and separating system-short-rasp-bar-plate-tooth drum with grid concave, including threshing and separating grain losses rate, power consumption and distribution of outlier along cylinder's axial direction. Lastly, we apply a multi-objective optimization on the system based on MATLAB optimum toolbox, so as to get the comprehensively optimistic operating parameters for it.Based on the investigation of characteristics of rice, analytical studying on the experimental results of two different types of threshing and separating system, we make out the differences of working performance of them, which deepens our understanding on working regularity of different threshing and separating systems. At the same time, the best working parameters are determined through establishing mathematical models and proceeding multi-objective optimization for the threshing and separating system with short-rasp-bar-plate-tooth drum and grid concave. Moreover, all these research results provide some theoretical basis for further study on the threshing and separating system of rice combine, and play an important and realistic role in accelerating mechanization of rice harvest in our country.