火电机组热力系统的抽汽折合系数

CONVERSION COEFFICIENT OF EXTRACTION STEAM FROM THERMODYNAMIC SYSTEM OF THERMAL POWER UNITS

采用偏微分理论定义抽汽折合系数,它表征在定流量条件下纯热量从某级加热器加入系统时受排挤的抽汽量折合为等效汽耗量的比率,也反映了各段抽汽的品质。把辅助汽水成分分为4类,推导了抽汽折合系数通用矩阵,以便于计算机程序化计算。抽汽折合系数结合对应级的变热量等效热降,可进行循环汽耗率的计算,为循环汽耗率的计算提供了新的方法。同时,抽汽折合系数也可用于完成非再热机组热经济性的局部定量分析。以N100-90/535机组为例,进行了计算分析,验证了该方法的有效性。

Adopting the partial differential theory,the conversion coefficient of extraction steam has been defined,the said coefficient means the ratio of the squeezed extraction steam converting to equivalent steam consumption when pure heat from heater of one stage joins into the system under constant flow condition,and reflecting also the quality of extraction steam from each stage.Dividing the components of auxillary steam-water into four kinds,the generalmatrix for conversion coefficient of extraction steam has been derived,so as to realize the calculation of computerized programme,providing a new method for calculating the cyclic steam consumption.At the same time,the conversion coefficient of extraction steam can be also used to fulfil the local quantitative analysis of the economic efficiency for non-reheated units.Taking N100-90/535 unit as example,calculation and analysis has been carried out,verifying the effectiveness of said method.