汽轮机调节级通用特性曲线计算方法分析与研究

Analysis and Research on the Calculation Method of Universal Characteristic Curves of Steam Turbine's Governing Stage

汽轮机调节级通用特性曲线的计算是汽轮机热力计算的基础工作。通过对以往两种调节级通用特性曲线的计算方法进行分析、比较,总结出在实际应用中的注意事项,同时,对动叶临界流量公式应用时的注意事项进行重点分析,得出应考虑动叶速度系数对该公式影响的结论,并实现了在厂家不提供动叶速度系数的情况下应用经验公式对其进行计算。最后,针对以往计算汽轮机调节级通用特性曲线方法中存在的不足提出了改进的迭代算法,并通过对实例的分析验证了该迭代算法的可行性。

The calculation of universal characteristic curves of steam turbine＇ s governing stage is the basic work of the turbine＇s thermodynamic calculation. By analyzing and comparing two former calculation methods of governing stage＇ s universal characteristic curves in this paper, the precautions about these two methods are concluded when they are practically used. Meanwhile, this paper emphatically analyzes the precautions of the moving blade＇ critical flow computational formula when it was in application and obtains the conclusion that the velocity coefficient＇ s effect should he considered in this formula, it also employ experience formula to calculate the velocity coefficient of the moving blade even though the manufacturers did not provide it. Finally, an improved iterative algorithm are provided in this paper in allusion to the deficiencies exist in the previous calculation methods about governing stage＇ s characteristic curves, and the feasibility of this iterative algorithm are verified by analyzing the living example.