A ROTARY BLADE DESIGN FOR PADDY FIELDS WITH LONG RICE STRAW BASED ON EDEM

The paddy field machine uses excessive power during paddy field preparation because of the high distribution density of rice straw. In this study, a rotary blade is created to address this problem. The structural parameters of the rotary blade were designed and the dynamic analysis of the rotary blade's soil-cutting process was completed to establish a model of the rotary blade's power consumption. Through the model, the primary factors influencing the rotary blade's power consumption were identified. A composite soil bin model of rice straw‒muddy layer‒bottom soil was established in EDEM software, with the bending angle of the front blade, the working width of a single blade, and the thickness of the blade as the test factors. The straw burying rate, power consumption, and surface flatness after rotary tillage were used as evaluation indicators to conduct multi-factor simulation tests on the composite soil bin model. The optimized analysis of the test data showed that the optimal geometric parameters for the rotary blade were 49 mm working width, 108° front blade bending angle, and 4 mm blade thickness. A field verification test was carried out on the optimized rotary blade, and the test results showed that the surface flatness after rotary tillage was 3.25 cm, the qualified rate of rotary tillage depth was 93.3%, and the degree of mud mixing was 3.41 kg/dm 3 , which was suitable for the land preparation requirements of paddy fields.