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本文首先建立了在欧拉-拉格朗日框架下的格子-波尔兹曼/离散单元法(LBE-DEM)耦合方法,并用于模拟二维气固两相交叉射流.其中气相射流采用TD2G9模型的格子-Boltzmann方法进行模拟;颗粒相用拉格朗日方法跟踪,同时采用DEM方法计算颗粒之间的碰撞过程.在相同载荷率下选取了10,25,50三种Stokes数.本文重点研究了气固多相交叉射流中涡形态、颗粒分布形态的新特性、交叉射流颗粒反射流比率问题,分析了交叉射流涡运动、颗粒群形态和颗粒反射比率等特性及影响因素.研究发现交叉射流中颗粒分布表现为离散群集分布和离散点分布的共同分布特性;同时,在射流初期较大的颗粒浓度或同载荷下较小的颗粒St数的交叉射流可产生较大的反射比率,而在后期颗粒相反射比率则基本稳定.
In this paper, the lattice-Boltzmann-Discrete Element Method (LBE-DEM) coupling method is established under the Eulerian-Lagrangian framework and used to simulate two-dimensional gas-solid two-phase cross jets. Model lattice-Boltzmann method was used to simulate the particle phase with Lagrange method to track, while using the DEM method to calculate the collision process between the particles at the same load rate selected 10, 25,50 three Stokes number. The characteristics of vortex morphology and particle distribution in gas-solid multiphase cross jets and the ratio of cross jet jet reflow flow were analyzed, and the characteristics and influential factors of cross jet jet movement, particle swarm morphology and particle reflectance were analyzed. In the jet, the particle distribution is characterized by the distribution of discrete clusters and the distribution of discrete points. At the same time, the cross-jet with larger particle concentration or the smaller particle number St at the initial jet can produce a larger reflection ratio, In the latter part of the particle reflection ratio is basically stable.