采用压力传感技术测量鼓泡床中流体力学参数

引　言鼓泡床以其良好的传热、传质、相间充分接触和高效的可连续操作特性在许多领域得到了广泛应用 .在过去的 4 0多年里 ,人们采用许多测量方法(光导纤维、多普勒测速仪、电导法、压力传感技术 )对鼓泡床中的各种流动行为进行了大量研究 ,由于床层内流动的复杂性以及各测量手段间的差别 ,得出的结论不尽相同1] ,而且工业反应多数在高温、高压、非透明体系下进行 ,这限制了许多测量技术的应用 .压力传感技术以其适用范围广、所需仪器便宜、耐用、测量结果准确的特点在鼓泡床流体力学参数测量中得到了广泛应用床层塌落法是压力传感技术在鼓泡床流体力学参数测量中的一个重要应用 .Sriram和Mann2 ] 较早地将其应用于测量鼓泡床中的气含率 ;Fan等3] 也曾利用此方法测量鼓泡床内的固含率 .前人大都采用压力传感技术测量床层内的平均相含率 ,而采用此方法测量大小气泡分数和气泡上升速度的报道很少 .本文根据前人在此方面的研究成果并结合本实验的特点进行了这方面的研究1　实验装置本实验结合工业对二甲苯氧化反应器的特点设计并建立了其流体力学冷模实验装置 ,如图 1所示 .鼓泡床高 6 6m ,内径 0 3m .在鼓泡床一侧自...

APPLICATION OF PRESSURE TRANSDUCING TECHNOLOGY TO MEASUREMENT OF HYDRODYNAMICS IN BUBBLE COLUMN

Based on the multi-class bubble model and the assumption that bubbles rise in plug flow during dynamic gas disengagement, the function between gas holdup and time was obtained by using the pressure transducing technology. The plot obtained by the model agreed with the plot obtained by experiment. The pressure transducing technology is shown to be a good method for the measurement of hydrodynamics in a bubble column. The changes of gas holdup, large bubble holdup and small bubble holdup, bubble rising velocity with superficial gas velocity and liquid viscosity were obtained by using dynamic gas disengagement.