大颗粒流态化特性的实验研究

Investigation on characteristics of fluidization of large particles

通过对大颗粒流化曲线及床层高度的测试对大颗粒流化床的流化过程进行了研究。结果显示,大颗粒的流态化过程是一个渐进的过程,整个流化过程可以分为:床层高度恒定、颗粒位置调整、表面颗粒运动、节涌波动和完全流化5个阶段。由于颗粒自身特性的影响,导致大颗粒流化过程中的各个特征速度(如起始鼓泡流化速度和完全流化速度)产生了有别于小颗粒流化床的特性。

After measuring the fluidization curve and the height of fluidized bed, the process of fluidization of large particle was investigated. The results of the experiments showed that the process of fluidization of large particles is a gradual process, it can be divided into 5 stages, the stage of invariant bed height,adjusting particles position,the particles of bed surface moving,turbulence fluctuation and complete fluidization. As the characteritics of the large particles themselves, the characteristic velocity such as beginning bubble velocity, minimum fluidized velocity and complete fluidized velocity are different from the small particles.