火电机组回热系统抽汽压损对火用损分布的影响  

The influence of extraction steam pressure loss to exergy loss in reheating system of thermal power unit

作　　者：黄超 房林铁[2] 王慧兴[2] 

机构地区：[1]贵州西电黔北发电总厂,贵州毕节551800 [2]华北电力大学,河北保定071003

出　　处：《贵州电力技术》2012年第1期63-66,88,共5页Guizhou Electric Power Technology

摘　　要：抽汽压损是一种不明显的热力损失，对机组的热经济性产生一定的影响。假定抽汽口的压力不变，加热器端差不变，根据小扰动理论，定性分析抽汽压损对回热系统的影响。根据热力系统热平衡原理和汽水分布方程建立抽汽压损对回热系统抽汽系数影响的数学模型。根据火用平衡原理和火用分析法建立抽汽压损对火用损分布的影响的数学模型。以某电厂N1000—25／600／600机组热力系统为例，在TRL工况下，定量计算回热系统抽汽系数和火用损分布的变化。根据定量计算结果从理论上分析了抽汽压损对热力系统产生的影响。Extraction pressure loss is a kind of tmconspicuons heat loss,and has some impacts on the unit＇s thermal econotmy. Assuming the constant pressure, of extraction port and temperature difference of the heater, qualitative analysis about the influence of changes is made to extraction steam pres-sure loss to heat system according to small disturbance theory. From heating system heat balance principle and steam water distribution equation, it establishes the mathenutical model about the influence of extraction steam pressure loss to abstract coefficient of the reheating system. The mathematical motel about the influence of extraction steam pressure less to exergy loss distribution is established combining exergy balance principle and exergy analysis. The change on extraction coefficient and exergy loss of reheating system is calculated on a N1000 -25/600/600 unit thermal system in TRL condition. On the basis of quantitative results, it analyzes the effect of extraction steam pressure loss to heat system in theory.

关 键 词：回热系统 抽汽压损 汽水分布方程 火用平衡原理 小扰动理论 

分 类 号：TM62[电气工程—电力系统及自动化]