汽轮机通流效率与机组热耗率关系的计算

建立汽轮机组变工况热力计算程序,并给出各缸效率与热耗率关系的数学模型,对上海汽轮机厂600 MW超临界汽轮机进行热力计算,分析通流性能变化与热耗率的关系。计算结果显示:级组效率变化与热耗率及本缸效率变化量成线性关系;级组承担功率越大、越靠近排汽端,则级组效率变化对热耗率与本缸效率的影响越大;低压缸效率改变对热耗率的影响最大,高压缸其次,中压缸最低;基于数学模型的计算结果与变工况热力计算基本一致,表明该数学模型计算精度很高。

The Relationship Between Flow Path Performance and Heat Consumption Rate of Steam Turbine

This paper established a thermodynamic calculation program for steam turbines operating under different conditions. Besides, a thermodynamic model was also presented to calculate the change of heat consumption rate due to turbine efficiency deviation. Thermodynamic calculation for a 600 MW supercritical steam turbine manufactured by Shanghai Steam Turbine Company was conducted in detail. The results show that linear relationship exists between the variation of stage group efficiency, the heat consumption rate, and the turbine efficiency. In the same cylinder, the more power the stage group takes on, the larger influence it has on the heat consumption rate and turbine efficiency. LP turbine efficiency has the most significant influence on the unit heat consumption rate, HP turbine efficiency secondary, and IP turbine efficiency in the end. Based on the thermodynamic model, the change of heat consumption rate was calculated, and the results were in the agreement with thermodynamic calculation program, which means that the present thermodynamic model is accurate enough for application. This work can serve as the foundation for analyzing unit heat consumption rate variation caused by performance deviation in turbine flow path.