Analysis of large deflection nonlinear elastic deformation and load theory research of flip-flow screen panel

Aiming at the problem that there exist lacks of analysis of the elastic properties of screen panel materials and research on the influence of mineral impact on the deflection changes of screen panel in response to the theory of large deflection deformation of flip-flow screen surface. Considering the scalability of the flip-flow screen panel material, a theoretical model of large deflection nonlinear elastic deformation of the screen panel is established. Combining with the external excitation sine displacement function, the time-domain expression of the screen panel with different amplitudes and frequencies is proposed for the first time. A testing platform for the dynamic characteristics of the flip-flow screen panel is built to verify the accuracy of the theoretical model in describing the deflection change process of the screen panel, and the optimal vibration parameters of the large deflection elastic deformation theory in describing the dynamic characteristics of the screen panel is clarified using the response surface optimization method. Based on the theory of large deflection elastic deformation of unloaded screen panel, a deflection variation theory of screen panel when particles collide with screen panel is proposed, and the deflection curve of screen panel with different motion states under particle impact force is calculated. Then the influence of different physical parameters on the local deformation degree of the collision point between the screen panel and mineral particles is revealed, and the accuracy of the theoretical expression of the deflection change of the screen panel under the collision of particles is verified through simulation experiments in describing the dynamic characteristics of the screen panel using different initial constraints. The research results show that the error rate of the experiments and theory of large deflection elastic deformation of screen panel under dynamic conditions is below 6%. The theoretical and experimental error rates of large deflection elastic deformation of the screen panel under dynamic conditions decrease with the increase of amplitude and frequency, but this change is nonlinear. When the amplitude is 7.33 mm and the frequency is 11.75 Hz, the error rate between the theoretical and experimental values at each measuring point reaches the lowest, and the average error rate at the midpoint of the screen panel is less than 3%. The incident angle of particles, the position of the impact point, the installation angle of the screen panel, and the operating state are important factors that affect the degree of local deformation of the screen panel during impact. Theoretical proof is shown that when the inclination angle and particle incidence angle of the screen surface installation are large, and the screen panel near the midpoint position move to the highest point, the collision between particles and the screen panel can obtain the maximum initial kinetic energy, and there is an average error of less than 4 mm between deflection deformation theory of the screen panel after collision in describing the impact point position and simulation results.