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了解有旋和无旋突扩气粒两相详细湍流结构对控制燃料-空气混合、火焰稳定以及燃烧污染物生成很重要.周力行等曾经对其中的两相时平均流场和湍流特性进行过雷诺平均的RANS模拟和测量的研究,但是BANS模拟不能给出详细的两相湍流的瞬态结构.本文建立了二阶矩两相亚网格尺度应力模型,对有旋和无旋同轴突扩气粒两相流动进行了双流体大涡模拟.大涡模拟统计结果得到的两相时间平均速度和均方根脉动速度得到了测量结果的实验检验.大涡模拟瞬态结果显示出有旋和无旋突扩两相流动湍流结构的不同.在有旋情况下,气体流动有多个回流涡,但是没有典型的拟序结构,而无旋情况卜的气体流动有典型的拟序结构.两种情况下的颗粒流动都几乎没有涡结构.“,”Detailed gas-particle two-phase turbulence structure with and without swirling flows is very important to control fuel-air mixing,flame stabling and combustion pollutant producing in combustion chamber.Lot of RANS and experimental studies had been carried out for time-averaged mean flow flied and turbulence behavior of two-phase flow.But,detailed instantaneous two-phase turbulence structure could not be observed.A second-order-moment subgrid-scale stress model(SOMSGS) based on two-fluid approach is proposed to simulate numerically for coaxial sudden-expansion gas-particle flows with and without swirling flows using large eddy simulation(LES).LES statistical results of two-phase time-averaged mean velocity and root-mean-square(rms) velocity are validated by experimental data.The different detailed turbulence structures are obtained.With swirling flow, no typical coherent structure is observed and lots of re-circulating eddy are found.Without swirling flow,typical coherent structure of gas phase is found.Furthermore,eddy structure of particle phase flows is not obvious for both swirling and not swirling flow.