空冷汽轮机末两级变工况三维流动的数值模拟

Numerical Simulation of 3-Dimensional Flow in Last Two Stages of Air-cooled Steam Turbines

采用三维粘性数值模拟方法对变工况下空冷汽轮机末两级流动进行了模拟,研究了效率和脱流高度等重要参数的变化规律,着重分析了设计点和小容积流量工况时的三维流场。通过分析了解了机组在变工况运行时末级流动的特点,为空冷汽轮机末级叫片的设计和优化提供了依据。

Flow in last two stages of air-cooled steam turbines under varying load conditions is being studied with the help of numerical 3-dimensional viscous flow simulation methods. The laws that govern variations, like efficiency and blade＇s height, at which flow separation occurs, are being studied; specially analyzed in detail were the 3-dimensional flow fields under design and low volume flow conditions. Understanding of the particularities of flow conditions in the last stages under varying turbine load conditions are gained by an analysis, which may serve as a reference for design and optimization of the last stage blades of air cooled steam turbines. Figs 8 and refs 5.