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在较宽操作条件范围内对16m高提升管中气-固两相流(空气-FCC颗粒)的压力梯度进行了实验测试，进一步揭示了快速流态化和密相气力输送这两种流动形态的动力学特征及其与操作参数的关系。结果表明，在表观气速增大的过程中气固提升管中的轴向压力梯度并非总是不断趋于均匀分布；提升管高度对从快速流态化到密相气力输送状态的过渡有重要影响，对于给定的表观气速，提升管高度增加将使过渡点所对应的颗粒循环量和床层颗粒浓度都减小。本实验条件下所有过渡点对应的床层颗粒浓度较为一致，平均为0.0104，并由此得到过渡点操作参数Ug与Gs的关联式。本文研究表明，在以往工作基础上进一步研究提升管高度对流动行为的影响极有必要。
The pressure gradient of gas-solid two-phase flow (air-FCC particles) in a 16m high riser was tested over a wide range of operating conditions, further revealing the two flow patterns, fast fluidization and dense phase pneumatic conveying Kinetic characteristics and its relationship with operating parameters. The results show that the axial pressure gradient in the gas-solid riser does not always tend to be uniformly distributed in the process of increasing the apparent gas velocity. The transition of the riser height to the state of rapid gas-phase to dense-phase pneumatic conveying Importantly, for a given superficial gas velocity, the increase in riser height will result in a reduction in both the particle circulation and the bed particle concentration at the transition point. Under this experimental condition, the bed particle concentration corresponding to all the transition points is relatively uniform, with an average of 0.0104, and the correlation between the operating parameters Ug and Gs at the transition point is obtained. The research in this paper shows that it is necessary to further study the effect of riser height on flow behavior based on previous work.