220 MW汽轮机组5段抽汽温度异常数值模拟研究

Study on Numerical Simulation of Temperature Anomaly of Steam Extraction in the Fifth Stage of 220 MW Steam Turbine Units

通过数值模拟方法替代现场的大量试验来分析汽轮机5段抽汽温度异常,结果表明:5段抽汽温度异常是由于汽轮机轴封1段漏汽“挤压” 5段抽汽所致;在采取降低轴封1段漏气压力或增加机组供热负荷措施后,5段抽汽温度恢复至运行值。数值模拟方法为燃煤电厂对于以蒸汽为介质的T型管道发生异常时的处理方法提供了一定的借鉴。

Numerical simulation method is used to replace a large number of field tests to analyze the temperature anomaly of steam extraction in the fifth stage of steam turbine.The results show that the abnormal temperature in the fifth stage is caused by the leakage of steam in the first stage and the“extrusion”of steam in the fifth stage of the turbine shaft seal.After measures are taken to reduce the leakage pressure of the first stage of the shaft seal or increase the heating load of the unit,the extraction temperature of the fifth stage is restored to the operating value.The numerical simulation method provides some references for the treatment of abnormal conditions of T-type pipeline with steam as the medium in coal-fired power plants.