两相圆湍射流颗粒弥散与速度相似性大涡模拟

Large-eddy simulation of particle dispersion and velocity similarity in a two-phase round turbulent jet

气相采用大涡模拟方法、颗粒相采用拉格朗日轨道模型,对高雷诺数两相圆湍射流进行了数值模拟,研究了一种中等Stokes颗粒在大尺度涡结构中弥散特点以及两相速度统计特征.研究表明,颗粒弥散同时受流动涡结构和颗粒惯性决定,颗粒在涡结构的边缘或者涡与涡交织区域颗粒数密度高,形成倾向性分布.沿中心轴线两相平均速度衰减不同,颗粒相速度衰减慢于气相.射流近场两相速度沿径向变化显著,在射流远场两相平均速度都具有相似性,沿径向颗粒相平均速度衰减慢、分布平稳.

A high-Reynolds two-phase round turbulent jet was numerically simulated by means of large eddy simulation for gas-phase and particle trajectory model for particle-phase.The dispersion behavior of particles with median Stokes number in large scale structures was studied.Two-phase statistical velocities were compared with each other.It s shown that particle dispersion is dominated both by large eddy structures and particle inertia,resulting in a high particle concentration distribution in the edge of vortex s...