颗粒惯性聚集中惯性升力的特性研究  

Investigation on the behaviors of inertial lift inducing inertial focus of particles

作　　者：王企鲲[1] 李海军[1] 李昂[2] 孙仁[2] 

机构地区：[1]上海理工大学能源与动力工程学院,上海200093 [2]上海交通大学工程力学系,上海200240

出　　处：《水动力学研究与进展（A辑）》2014年第5期530-535,共6页Chinese Journal of Hydrodynamics

基　　金：国家自然科学基金(11372186);国家教育部博士点基金(20113120120003)~~

摘　　要：该文基于Carlo等提出的"相对运动模型"对颗粒惯性升力的形成机制与动力学特性进行数值研究,揭示了惯性升力的构成特性,并提出了颗粒稳定聚集点的水动力学判据。研究结果表明,惯性升力由"压力分量"与"剪应力分量"构成,然而这两种升力的横向分布特征截然不同。压力分量具有与惯性升力类似的横向分布特征,是诱发颗粒惯性聚集真正的力学成因。此外,惯性升力的零点并非是颗粒形成惯性聚集的必要条件,只有当此零点满足颗粒稳定聚集运动的判据时,他才是稳定的聚集。利用这个判据能很好地解释小粒径颗粒不存在稳定聚集的水动力学原因,并有助于促进对管道内颗粒水动力学行为的研究,以及深化对低Re数管流中颗粒输运现象的认识。The dynamic behaviors and formation mechanism of the inertial lift exerting on rigid particles are numerically investigated in this paper based on a numerical approach proposed by Carlo. The composition of the inertial lift and the hydrodynamics criterion for the stable focus of particles are also proposed. Numerical results demonstrate that the inertial lift can be divided into a ＇shear stress component＇ and a ＇pressure component＇ while their transverse distribution characteristics are quite different. The pressure component with the same transverse distribution characteristics as the inertial lift is a critical formation mechanism for the inertial focus of particles. It is not a necessary condition to induce the inertial focus of particles that there are zero-inertial-lift transverse positions in the pipe unless the hydrodynamics criterion for the inertial focus of particles can be satisfied on those positions. Based on this hydrodynamics criterion, the reason why the small particles will not be focused can be reasonably explained. These results are expected to improve the prediction of the hydrodynamics behaviors for the particles inside a bounded flow and deepen the understanding of the transport phenomena of particles moving in a low-Reynolds-number pipe flow.

关 键 词：惯性升力 颗粒惯性聚集 低Re数流动 管道流动 数值研究 

分 类 号：O359[理学—流体力学]