汽轮机中压排汽缸气动分析研究

Study on Aerodynamic Analysis of IP SteamTurbine Exhaust Hood

中压排汽缸的气动性能直接影响汽轮机的整体效率,文章对单独排汽缸和汽轮机中压末级叶片、叶顶汽封耦合排汽缸进行数值对比分析,介绍了末级动叶片因旋转所带来的对排汽缸气动性能的变化以及不同的汽封汇入排汽缸的流动方式对排汽缸气动性能的影响。CFD数值研究表明,耦合末级叶片的数值模拟结果对中压排汽缸的流场结构影响是不可忽略的,在今后的排汽缸气动设计及优化工作中需考虑末级叶片的影响;叶顶汽封漏气汇入排汽缸的方式对排汽缸的进口条件影响较大,在以后的优化工作中需考虑叶顶汽封的影响。

The aerodynamic performances of IP exhaust hood directly affect the overall efficiency of steam turbine. In this paper,numerical analysis for single cylinder and single channel of stator、 rotor and blade tip sealing of IP last stage coupling with exhaust hood has been done, and the change of aerodynamic performances of IP exhaust hood caused by the rotation of the last stage rotor and different flow models in blade tip sealing into the cylinder have been introduced. CFD simulation results show that the blade of IP last stage coupling with exhaust hood has a significant impact on flow field in IP exhaust hood, the effect of the blade of IP last stage should be considered in the future aerodynamic design and optimization of the exhaust hood. The flow models in blade tip sealing into the cylinder has a certain influence on inlet. conditions of the exhaust hood, the effect of tip leakage on blade tip sealing must be taken into account in the future aerodynamic optimization of the exhaust hood.