建立了高0.8m,截面为0.1m×0.01m的可视化浆态床实验系统,采用空气、水和玻璃粉作为浆态床中气液固三相,研究了颗粒粒径为58-75μm和106-150μm,固相体积分数为3%和9%时的宏观流动特性。试验获得了不同物料体系下的床层压降随气体雷诺数的变化规律,同时得到了颗粒浓度对流型转变气速的影响。找到均匀流流型向过渡流型转变的第一转变点和从过渡流型向非均匀流型转变的第二转变点的取值范围。结果表明:三相体系的压差值随着气体雷诺数的增大而趋于一个稳定值,颗粒粒径增大会使体系压差值增大;固体颗粒浓度的增加,会使第二转变点取值减小,而颗粒粒径对流型转变气速影响很小。固相浓度的增加,会加快三相体系的失稳,在更低的气速下进入到非均相湍动流动状态中。
A visual bubble column with 0.8 m height, a length of 0.1 m and a width of 0.01 m was built. Air, tap water and glass powder constituted the gas, liquid and solid phase respectively. Macroscopic flow characteristics were studied with particle diameters of 58-75 μm and 106-150 μm and solid phase volume fractions of 3% and 9%. The curves of pressure drop changed with the gas Reynolds number in different conditions were obtained, and the effects of particles on the flow regime transition points were studied. second transition point were found. Results show system reached stable values with gas Reynolds The values of the first transition point and the that: the differential pressures of the three-phase number increased, and the values of differential pressure increased when increasing the particle diameter; when solid phase concentration increased, it decreased the value of the second transition point, while, particle diameter had little effect on the transition points. Solid phase concentration increase will make the three-phase system become unstable more easily, and make the flow regime change to the heterogeneous flow at a lower gas velocity.