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, free grain and cumulative gain  along the axial threshing drum  was obtained. The loss of separation  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 wereconducted 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.