CAJ | 학술논문

采用离散单元法模拟了二维提升管内湿颗粒的流动和团聚特性。考虑颗粒所受重力、颗粒间(颗粒与壁面间)的碰撞力、摩擦力、液桥力以及气体对颗粒的曳力和浮力。预测提升管内湿颗粒的流动行为，得到不同含湿量下颗粒浓度和轴向速度的分布，并且定量分析了湿颗粒的团聚特性。结果显示：湿颗粒在提升管内呈现边壁浓、中心稀的环核流动结构；由于液桥力的存在，提升管内湿颗粒出现团聚现象，且颗粒以单颗粒和聚团2种方式运动；含湿量对颗粒聚团存在时间、聚团时间份额和聚团生成频率有较大的影响。
채용리산단원법모의료이유제승관내습과립적류동화단취특성。고필과립소수중력、과립간(과립여벽면간)적팽당력、마찰력、액교력이급기체대과립적예력화부력。예측제승관내습과립적류동행위，득도불동함습량하과립농도화축향속도적분포，병차정량분석료습과립적단취특성。결과현시：습과립재제승관내정현변벽농、중심희적배핵류동결구；유우액교력적존재，제승관내습과립출현단취현상，차과립이단과립화취단2충방식운동；함습량대과립취단존재시간、취단시간빈액화취단생성빈솔유교대적영향。
The wet particles flow and agglomerate characteristics in a two-dimensional riser was numerically simulated by discrete element method (DEM). The force acting on particle included gravity, particle-particle or particle-wall interactions (i.e. contact force, friction force and liquid bridge force), drag force and pressure gradient force. In this paper, the flow behavior of wet particles was predicted, and the distribution characteristics of particle concentration and axial velocity at various moisture contents were obtained. Then, agglomeration characteristics of wet particles were analyzed quantitatively. The results indicate that a core-annulus flow structure with a dense phase near the walls, and a dilute phase in the center are formed in wet particles riser. The results show that due to existence of the liquid bridge force, it appears wet particles agglomeration phenomenon, and the motions of wet particles in the riser have two ways with single particles and agglomerates. There are significant influences of moisture content on agglomerate duration time, agglomerate time fraction and frequency of agglomerate occurrence.