循环喷动流化床空隙率分布

VOIDAGE PROFILES IN SPOUTED-FLUIDIZED BED WITH DRAFT TUBE

采用PC - 4光导纤维颗粒测浓仪对循环喷动流化床循环管和沉降室中空隙率进行测定 ,得出沉降室内部空隙率随操作气速的增加基本保持不变 ,近似等于最小流化空隙率 ;在无沉降室充气时 ,循环管内部的空隙率随操作气速的增大基本保持不变 ,循环管顶部的空隙率则随着气速的增大而逐渐增大 ,在有沉降室充气时 ,循环管内部的空隙率随气速的增大逐渐减小 ,循环管顶部的空隙率随气速的增大保持不变。

The PC 4 fiber optic probes is used to measure voidage profiles in the spouted fluidized bed with a draft tube employing millet ,glass bead and resin as test materials.It has been found that the voidage in the downcomer is approximatelly equal to the minimum fluidization voidage(ε mf )with increasing solid partical velocity whenever the gas supplied to the downcomer is present or not .The voidage in the draft tube remains the same with the solid partical velocity when the gas supplied to the downcomer is present and decreases when it is absent,while the voidage above the draft tube increases with the solid partical velocity when the gas supplied to the downcomer is present and remains the same when it is absent.