Structural Dynamics of Corn Threshing Drum Based on Computer Simulation Technology

We designed a new type of composite threshing drum to reduce the kernel broken rate of corn. Dynamic balance correction and modal analysis were performed for the corn threshing drum to verify the performance, reliability, and safety of threshing. Through finite element simulations of dynamic balance, we obtained the resultant support reaction force at the two ends of the threshing drum. The dynamic unbalance quantity was determined, and dynamic weight compensation was conducted based on the simulation results. The dynamic balance test demonstrated the feasibility of the dynamic balance design of the threshing drum. Modal analysis identified the vibrations of the threshing drum in a free state. The natural frequencies of each mode and the maximum vibration displacements were calculated. Accordingly, the dangerous range of rotational speeds and vibration-induced deformation at lower modes were determined. The test indicated that the dynamic balance of the corn threshing drum conformed to the national design code. The actual rotational speed of the threshing drum did not fall into the dangerous range. The displacements caused by both radial and axial vibrations do not cause interference. Thus, the design of the corn threshing drum was safe and reliable.