汽轮机通流部分结垢与热力参数变化的关系分析

Analysis on Relationship between Scaling and Variation of Thermal Parameters in Steam Turbine Flow Passage

汽轮机通流部分结垢会导致热力参数发生变化,降低汽轮机运行的经济性和安全性。通过对热力参数的监测与利用,可以对通流部分的结垢情况进行诊断。对不可压缩流动分析公式进行比较验证,并应用该公式对某630 MW超临界机组通流部分进行诊断:根据热力参数的变化对机组进行定性分析,初步判断通流部分结垢;利用当量通流面积诊断方法对通流部分进行定量计算,判断出结垢的具体位置和程度;诊断结果与停机揭缸情况吻合。

Scaling issues occurred in the steam turbine flow passage can lead to the variation of thermal parameters and thus influence the economy and safety of the steam turbines. Through monitoring and utilizing theses thermal parameters, analysis on scaling issues in the steam turbine flow passage is carried out. The equations for incompressible flow, which are verified firstly, are utilized in this paper to analyze the actual conditions of the flow passage of one 630 MW supercritical steam turbine. The scaling issues are preliminarily identified through qualitative analysis focusing on the variation of thermal parameters. Then, quantitative calculation employing the equivalent flow area diagnosis method is performed so as to figure out the location and the severity of the scaling issues. The analysis results are consistent with the inspection results obtained during the maintenance period of the steam turbine.