Optimization of Design Parameters of Press Wheel Attached Straw Cutting Mechanism for Rice Residue in Simulated Field Condition

The main challenge with conservation tillage methods, such as no-tillage and minimum tillage planting is placing seeds beneath crop residue with proper seed-soil contact. Sowing technologies in conservation tillage can improve soil quality, reduce erosion, and save time and fuel. However, crop seed germination is negatively affected by plant residues on the soil surface, so these residues must be managed. To overcome this problem, three types of coulter blades were tested in a soil bin to assess their ability to cut paddy residue, considering factors such as speed ratio and the number of press wheels. Horizontal and vertical forces, torque applied, and power requirements were calculated for selected blades at different speed ratios, numbers of press wheels, and different levels of rice residue during operations. Various parameters, such as the type of cutting coulter blades, speed ratio, number of press wheels, and different levels of rice residue density, were optimized toachieve maximum paddy residue cutting efficiency and minimum straw clogging. The optimized values of horizontal force (12.88 kg), vertical force (33.45 kg), torque applied (12.48 Nm), and power requirement (310.6 W) were obtained at the optimal design parameters: speed ratio (7.70), number of press wheels (2), and straw density (500 kg/ha). The maximum cutting efficiency of 100% and the minimum straw clogging of 1.80 kg/ha were achieved for a plain coulter blade.