Testing, Evaluating and Simulate the Performance of the Newly Designed Drum for a Sunflower Threshing Machine

The stationary thresher machines are widely used worldwide in threshing and separating many crops; they proved to have a high performance, especially in small spaces. The threshing drum is the essential working device of the thresher and plays a fundamental role in threshing efficiency, consumed specific energy, machine productivity, and seeds loss. In this study, a structure of sunflower thresher (open style drum with 45 incline degree loop teeth) was tested, and evaluated for performance under different drum rotational speeds (150, 200, 250, and 300 rpm) and different concave clearances ( 10, 15 and 20 mm). The thresher structure and operating parameters were assessed and optimized concerning damaged and unthreshed seed percentage, threshing efficiency, consumed specific energy, and machine productivity. The obtained results revealed that increasing cylinder rotating speed positively related to threshing efficiency, power requirements, and machine productivity while increasing concave negatively related to threshing efficiency, power requirements, and machine productivity. The highest efficiency of 97.40 %, the maximum productivity of 434.50 kg/h, and the lowest consumed specific energy of 6.85 kW.h/t were obtained at the operational condition of 300 rpm drum rotational speed 10 mm concave clearance. Buckingham's π theorem was followed to find an equation to predict the threshing efficiency theoretically, resulting in an equation with an R2 value of 0.8892. These developments were an excellent choice to uprising the performance of the original thresher drum.