Study On Touching Mechanism Of Dry Particles

Vibrating screen is the machinery which make particles loose, stratification,touching and penetration by vibrating and achieve the separation of particles in theprocess of convey materials. The material touching is the main factor to affect thepenetrating probability and the screening efficiency. Exploring the screeningmechanism by the touching mechanism research is a new train of thought.In this paper, the numerical simulation researches about the process of vibratingscreen have been done using the EDM (Discrete Element Method), which analyzethe effects of the various parameters on touching and research the touchingmechanism, the main works are as follows:1. In the paper, the concept about the touching screen frequency of the materialand average touching screen probability has been defined to research the mechanismof touching vibratory screen. The relationship curves between frequency of touchingvibratory screen with sieving parameters and average probability of touchingvibratory screen with sieving parameters were established, which analyze theprocess of materials touching the screen.2. With single-factor experiments, the effect of the structure parameters and thevibrational parameters on touching have been system analyzed in detail, and themathematical model between the parameters and touching have been builded.3. Based on single-factor experiments, the interaction of orthogonal experimentswere designed and practiced, in which both three parameters were taken three levelsand each category parameters was designed27experiments. Optimal combinationparameters about the touching screen frequency have been gained by numericalsimulation. Significantly effect of parameters on touching screen have beenanalyzed.4. The law of touching screen gained by the simulation coincides with the result of experiment, which explains the touching mechanism very well. In the paper, theestablished characteristic quantities of touching screen analyze the law of sievingprocess very well. It is new method of the analysis and study of the screeningmechanism.