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采用CFX商用软件及剪切应力输运湍流模型对燃气轮机中第一级透平的轮缘密封进行了稳态和瞬态流动特性的数值研究.对于稳态特性,数值研究了不同轮缘密封结构和转速对轮缘密封效率和无量纲密封流量的影响;对于瞬态特性,详细分析了压力、频率以及轮缘密封效率的分布规律.研究结果表明:轮缘密封效率随着无量纲密封流量的增大而增大;轴向和径向密封结构的最小无量纲密封流量变化范围分别为9.62×103~9.63×103和5.07×103~5.75×103,表明径向密封结构的密封效果优于轴向结构;随着轮盘转速的升高,最小无量纲密封流量增大;提高密封空气流量有利于减小轮缘腔室内的非稳定性,但对压力的周向分布和静叶尾迹区的分布影响很小;瞬态计算下获得的静盘面密封效率要低于稳态计算值.“,”This paper presents a numerical investigation on the steady and unsteady flow characteristics of rim seal for the first stage in gas turbine. The Reynolds-averaged Navier-Stokes equations, coupled with shear stress transport turbulence model, and a scalar equation are solved. In the steady-state conditions, the influences of rim seal structures and rotational speeds on the sealing effectiveness and non-dimensional sealing air mass flow have been numerically investigated. In the unsteady-state conditions, the pressure distribution, pressure-frequency and sealing effectiveness are discussed in detail. The results obtained in this study indicate that the sealing effectiveness increases with the non-dimensional sealing air mass flow. The minimum non-dimensional sealing mass flow for the axial rim seals and radial seals ranges from 9.62×103 to 9.63×103 and from 5.07×103 to 5.75×103, respectively. It means that the radial seals perform better than the axial ones in sealing effectiveness. The minimum non-dimensional sealing mass flow increases with the increase of rotational speeds. The increase of sealing air is conducive to reducing instability in the rim seal cavity, which has small influences on the circumferential pressure downstream the vane trailing edge. The unsteady-state sealing effectiveness is lower than that calculated in steady state.