关键词: 气流分级机, 迷宫密封, 气流密封, 相对分级精度, 数值模拟

Abstract:

Turbo air classifier was an ultra-fine grading equipment broadly applying in ultrafine classifying industry. However,the leakage phenomenon of coarse powder about classifier with traditional labyrinth seal was not eliminated. In this paper,impacts of end face sealing gap and gas sealing pressure change to different material classification effects were investigated,and the relative classification precision to evaluate the quality of classifying was used. Gas sealing fluid field was simulated by Ansys Workbench 15.0. The distribution of the gas sealing fluid field was presented by its velocity field and pressure field. Numerical simulation and experimental results showed that the relative classification precision decreased along with the increase of end face sealing gap. Optimum relative classification precision was obtained. Classifier could be normal operated under the condition of 3mm of end face sealing gap. The relative classification precision first increased then decreased along with the increase of gas sealing pressure under the condition of 3mm of end face sealing gap with gas seal. When gas sealing pressure was 0.15MPa,the relative classification precision of fly ash and slag was the highest. The failure of gas sealing pressure was 0.05MPa. The performance of classifier and classification effect was better under the condition of the same end face sealing gap and used gas seal. The relative classification precision of fly ash and slag increased from 0.202,0.187 to 0.458 and 0.408.

Key words: air classifier, labyrinth seal, gas seal, relative classification precision, numerical simulation