多组分气固射流床流动特性 Ⅱ流型的划分

在３００×５０×２６００ｍｍ的二维射流流化床中，使用压力波动的功率谱分析方法，考察了９种单一、双组分混合物物性因素（粒径、密度）、操作因素（射流气速、喷口直径、静床高度、环隙气量）对射流流化床的三种流型：气泡串、射流、喷流相互转变的影响。结果表明，在较低静床高时，随着射流气速的增大，射流床内流型由气泡串、射流过渡到喷流；而静床高较高时，射流气速增大仅由气泡串过渡到射流。环隙气量增大、粒径增大、密度增大，喷流流型出现较困难，最后得出了流型转变图及转变的定量关系式

FLOW CHARACTERISTICS IN GAS-SOLID JETTINGFLUIDIZED BED WITH MULTI-COMPONENT STUDY ON DIVISION OF FLOW REGION

The flow region division in a 300502600 mm two-dimensional jetting fluidized bed was determined using power spectrum density function PSDF Nine materials including four binary mixtures were used in this paper Effects of material property, such as particulate density and diameter, on transition of flow region were investigated Meanwhile, effects of operating parameters including jet gas velocity, conical gas volume, static bed height and nozzle diameter on region transition were also studied By measuring pressure fluctuation with differential pressure sensor and treating the sampling signals, the power spectrum density functions PSDF were calculated Based on dominant frequency f of PSDF, the curves f vs Z jet gas velocity u 0 can be obtained With low static bed height, there are two inflexions in the curve of fBZ and u 0 corresponding to jet flow and spout, respectively The results showed that a bubble plume, jet and spout appeared with low static bed height and an increasing of jet gas vel