Modeling and experiment to threshing unit of stripper combine

Abstract

The aim of this study was to establish the mathematical models to axial threshing unit of stripper combine harvester. The exponential distribution model of the un-threshed grain T_u(z), free grain T_f(z) and cumulative gain F(z) along the axial threshing drum z∈[0 L] was obtained. The loss of separation L_f was the free grain which had reached the end of the threshing unit but still not separated. On the designed testing equipment, experiments of threshing performances were conducted with the different feed rates and drum rotator speeds for the rice stripped mixtures. Experimental results showed that the distribution of the cumulative separated gain was in agreement with the simulation. The results were very useful for practical analysis of grain separation and damage as well as for threshing unit design and process optimization.

Key words: Stripping, combine harvester, threshing unit, model, experiment.