(1. 东北电力大学 能源与动力工程学院,吉林 132012;
2. 中国大唐集团科学技术研究院有限公司,北京 102206)
摘 要: 采用实验和理论分析方法,以Lacey混合指数作为混合评价指标,研究转速、填充率对椭圆型混合器内二元颗粒在滚落运动模式下径向混合的影响。结果表明:在波动混合阶段,椭圆型混合器的离心率影响颗粒的混合稳定性;同一工况下,椭圆型混合器在竖直位置和水平位置的颗粒动态休止角相等;填充率一定时,动态休止角随转速的增大而增大;填充率不大于1/2、转速一定时,同一位置的活动层自由下滑面长度随填充率的增大而增大;同一工况下,椭圆型混合器在竖直位置时的活动层面积大于水平位置时;位置一定时,活动层面积随填充率增大而减小,随转速增大而增大;当转速不变,颗粒的混合程度随填充率减小而提高。
关键字: 椭圆型混合器;二元颗粒;活动层;径向混合
(1. School of Energy Resource and Power Engineering, Northeast Dianli University, Jilin 132012, China;
2. Science and Technology Research Institute Co., Ltd., China Datang Corporation, Beijing 102206, China)
Abstract:In order to evaluate the quality of mixing, the effects of filling ratio and rotational speed on transverse mixing of binary granular in an elliptical mixer operated in the rolling regime were studied adopting experimental and theoretical approaches based on mixing index Lacey. The results indicate that the centrifugal rate of the elliptical mixer affects the mixing stability of binary granular in the wave mixing stage. For the same operating condition, the dynamic angle of repose in horizontal position and vertical position of the elliptical mixer are equal. When the filling ratio is constant, the dynamic angle of repose increases with the increase of rotational speed, however, the filling ratio is not larger than 1/2, the length of active layer with free surface increases with the increase of the filling ratio at the same rotational speed increasing. For the same operating condition, the area of the active layer in the vertical position is bigger than that in the horizontal position. The area of the active layer decreases with the filling ratio increasing, and increases with the rotational speed increasing in the same elliptical cylinder position. The mixing degree of granular increases with the decrease of filling ratio at a fixed rotational speed.
Key words: elliptical mixer; binary granular; active layer; transverse mixing