Study on the Flying Paddy Acting the Cleaning Wind (Part 1)

Abstract

The effectiveness of winnowing in the threshing unit can be improved by considering the trajectory of the grain and chaff, and then adjusting the flow of air accordingly. In this study, we aimed to understand the trajectory of a grain of paddy. We examined variations in the drag and lift coefficients due to variations in the direction of the grain. The results confirm that the drag and lift coefficient can be expressed as a trigonometric function of the direction. And we established equations to determine the trajectory in a two-dimensional plane. Terminal velocity was obtained from these equations. The results can be considered a reasonable value.