The unsteady spatially-developing process of a particle-laden turbulent planar jet at a moderate Reynolds number(Re＝13 000)，was numerically simulated by using an Eulerian／Lagrangian approach.The large eddy simulation (LES) was used to sim ulat e the turbulence of the continuous phase,where the motions of the large scale st ructures were solved directly through the incompressible Navier-Stokes equat ions and the effects of the unresolved scales were modeled by the standard Smagorins k y sub-grid-scale model.In order to visualize the coherent structures of the je t,as in the experiments,the transport equation for a passive scalar was also int r oduced and solved.Particles were tracked by computing the acceleration and motio n equations of the individual spherical particle within the computational domain in a Lagrangian way.Results show that a rich variety of coherent structures generated by the instability of the shear layer and their detailed developing process in the proximal region of the jet can be simulated by the LES technique.As a dilute p articulate planar jet flow is investigated in present work,the motions of partic les of different Stokes numbers is mainly determined by two factors,the inertia of particles and the coherent structure of the jet.The instantaneous distributi ve pattern of particles whose Stokes number is less than the order of 10 is clos ely related to the interactions between the particles and vortex.It is suggested to take into account such effects when the particle dispersion in shea r flows is studied.%采用Eulerian／Lagrangian方法，对空间发展的 气粒两相平面湍射流的非定常流动过程进行了数值模拟。以Re数为13 000的 平面不可 压缩湍射流流动为例，气相场采用大涡模拟(large-eddy sim ulaito n，LES)技术，直接求解大尺度涡运动的Navier-Stokes方程，小尺度涡 采用标准Smagorinsky亚格子模式模拟。为了示踪两相射流中气相的运动，同时 求解了标志物的浓度输运方程。颗粒相的运动用Lagrangian方法直接求解。大 涡模拟结果表明，在平面射流的过渡区及充分发展区存在丰富的拟序结构及其相互作用。对 于稀疏两相射流，不同Stokes数的颗粒运动规律和浓度分布取决于颗粒惯性和气相拟 序结构的共同作用。对于Stokes数小于10的两相射流，颗粒相的瞬时浓度场分布与拟 序结构密切相关，研究颗粒相的扩散应当考虑拟序结构的影响。
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