环管喷射干燥器的流体力学研究

Study on hydrodynamics of a loop-tube jet dryer

采用等动力取样法和改进的 BS 1型皮托管测定了加料条件下环管干燥器的流体力学性能 .试验条件 :送气量 2 0 0～ 2 75m3/ h,加料量 0～ 3 kg/ h.试验表明 :在送气量一定时 ,物料的加入导致气体的循环比下降 ,环管的总压降也随之减少 ;颗粒的循环比基本上不受送气量和加料量的影响 ;随加料量的增加 ,固气质量比显著增加 ,但基本不随送气量变化 .通过试验观察到在气固混合室内颗粒存在粘壁现象 。

The hydrodynamics of a looptube jet dryer was measured at the condition of feeding solidmaterial with the isokinetic sampling method and BS1 pitol tube. The ranges of gas volume rate and solid feeding rate are 200~275 m 3/h and 0~3 kg/h, respectively. The experimental results show when gas volume rate keeps constant the feedin of solid material leads to decrease of the gas circulation ratio and the total pressure drop of looptube dryer. Both the gas volume rate and the solid feeding rate don't almost influence upon the solid circulation ratio, and the mass ratio of solidgas obviously increases with solid feeding rate and almost keeps constant. Besides, the phenomenon of solid's adheringtowall in gassolid mixing space was observed. It is considered that the configuration of nozzle is main factor.