The Effects of Some Mechanical Parameters of a Developed Millet Thresher on Millet Threshing and Cleaning Efficiencies

Abstract
Some mechanical and process parameters of a developed millet thresher have been optimized using a numerical optimization technique. The machine threshes millet panicles and cleans the grains from the straw. The speed of threshing and the number of pegs attached to the threshing drum were mechanical parameters investigated, while the moisture content was the process parameter under investigation. Threshing efficiency, cleaning efficiency, and percentage losses were used as performance characteristics while investigating these parameters. A central composite rotatable design was used in the experiment (CCRD). The results of the experiments revealed that the speed of threshing and the number of beater pegs had significant positive effects on threshing efficiency, whereas the millet panicle had significant negative effects. The speed of threshing and the number of beater pegs had considerable positive effects on threshing efficiency, whereas the millet panicle had large negative effects, according to the results of the studies. Also, a combination of a speed of 1590 rpm, 28 beater pegs, and a millet panicle moisture of 15% resulted in the maximum cleaning efficiency of 98.31%. The cleaning speed had a positive substantial effect on the cleaning efficiency, although the beater pegs and moisture content had small effects. The optimum speed of 1730 rpm, number of pegs of 35, and millet moisture content of 13.5 percent for threshing efficiency of 91.41 percent, cleaning efficiency of 97.87, and desirability of 0.997 were achieved using numerical optimization. The study’s findings include standard input machines and processing variables that produce the best machine output.