Abstract: On the basis of establishing the narrow level experimental system of turbo air classifier，and in order to study the effects of process parameters on particle size distribution and productivity of narrow level product in turbo air classifier，the rotation speed difference of two-stage rotor cages and the second wind speed of the second classifier were used as experimental factors. Particle size distribution curve of the product was used as experimental index. Narrow level experiment system of turbo air classifier was investigated. The experimental results showed that with the rotation speed difference decreasing，the particle size distribution curve of the product became narrower. When the second wind speed increased，the content of the fine powder of product reduced and the particle size distribution curve of the product became narrower. In addition，the relationship among productivity，uniformity of narrow level product and rotation speed difference was studied. Results showed that with rotation speed difference decreasing，productivity of narrow level product decreased and the uniformity increased. Further study indicated that there was a best rotation speed difference ?n0，under which product could be able to both meet the requirement of uniformity and productivity.

Key words: vortex air classifier, narrow level, rotation speed difference, the second wird

摘要： 在建立涡流空气分级机的窄级别实验系统的基础上，为了研究工艺参数对窄级别产品粒径分布和产率的影响，确定了以两级分级机的转笼转速差和第二级分级机的二次风速为实验因素，以产品的粒径分布曲线为实验指标，对涡流空气分级机的窄级别实验系统进行实验。实验结果表明，随着转速差的减小，产品的粒径分布曲线变窄；随着二次风速的增大，产品中的细粉含量减少，粒径分布曲线变窄。进一步研究了窄级别产品的产率、均匀度和转速差的关系。结果表明，窄级别产品的产率随转速差的减小而降低，均匀度随转速差的减小而增加。发现存在一个最佳转速差?n0，在这个转速差?n0下得到的产品能同时满足物料的均匀度和产率的要求。实验结果对窄级别产品的制备具有一定的指导意义。

关键词: 涡流空气分级机, 窄级别, 转速差, 二次风