Investigating Grain Separation and Cleaning Efficiency Distribution of a Conventional Stationary Rasp-bar Sorghum Thresher

Abstract

A stationary grain thresher was developed and used to study grain separation and cleaning efficiency distribution of the cleaning unit, fractionated by sieve and horizontal air stream, along the sieve length. The influence of feed rate, m, air speed, VA and sieve oscillation frequency, FS on cleaning efficiency of sorghum was explored. Grain separation along the sieve can be divided into three sections: increasing, peak and decreasing sections. Results showed that cleaning efficiency decreased with increasing sieve oscillations frequency and feed rate respectively. Cleaning loss increased with increasing sieve oscillation frequency, feed rate and air speed.