核电汽轮机功率背压特性计算方法的探讨

Discussion of Power/Back Pressure Characteristic Calculation Methods for Nuclear Steam Turbine

分析了背压变化对核电汽轮机功率影响的机理。对背压功率特性的几种简化计算方法进行了研究,对部分方法分别进行了局部优化,以某百万核电汽轮机为算例验证了优化的效果。对几种方法进行了综合比较,分析了其优、缺点。通过计算得出排汽干度变化对功率变化的影响可以忽略,而末级抽汽量变化的影响不能忽略的结论。

This paper analyzed mechanism of the influence on nuclear steam turbine power of the back pressure variation. Several simplified calculation methods for power/back pressure characteristics are researched and some of them are optimized, the effect of the optimization is verified via the calculation example for a 1000MW nuclear steam turbine. General comparison of these methods is made and advantages and disadvantages are analyzed. Through the calculation result 2, the conclusion that influence of the variation of the exhaust steam dryness on power change can be neglected, but the in- fluence of last stage extraction steam mass can not be neglected.