Abstract: For studying the conveying characters of cut tobacco in a closed flow valve,a set of closed flow valve for cold status test was established to study the effects of its working parameters,including fluidizing air flow,loosening air flow,side air flow and opening area,on the throughput of cut tobacco.The results showed that:1) the throughput of cut tobacco positively correlated with fluidizing air flow,loosening air flow,side air flow and opening area,and under the same conditions,the throughput was in the order of expanded cut tobacco>cut stem>cut tobacco;2) by dimensional analysis,the empirical equations between the throughput of cut tobacco and each working parameters were obtained,the results calculated by these equations well agreed with the experimental data with a correlation coefficient of 0.96.