关键词: 分级式冲击磨, 锤头数量, 锤头高度, CFD数值模拟

Abstract: The classify-impact mill possesses the advantage of high output. It is also widely used in crushing industry. However,the study of classify- impact mill is still insufficient. The grinding experiment of LNI-66A classify-impact mill was finished in this paper. The results showed that its production was higher than 4 beaters or 8 beaters when 2 beaters were used in classify-impact mill. As for the height of beaters,the production was higher than 10mm,20mm,40mm and even 50mm when the height of beaters was 30mm. Ansys Workbench 15.0 was used for numerical simulation of crushing cavity in this study. The distribution of the crushing cavity flow field presented by its velocity field and pressure field,and the influence of the flow field in grinding area caused by the parameters of beaters were discussed in this paper. Simulation results showed that the radial velocity of grinding area changed little while the pressure increased with the increase of the number of beaters. The crushing efficiency and powder production decreased on account of the increase of the number of beaters. The velocity of rising air near beaters and the crushing areas of beaters would be affected by the height of beaters. The velocity of rising air near beaters could reduce the crushing efficiency, while the crushing areas of beaters could increase the crushing efficiency,showing that there was a better choice between the two aspects. As a result,the height of beaters cannot be higher or lower and there was a better value in it.

Key words: classify-impact mill, the number of beaters, the height of beaters, CFD numerical simulation