耦合喷射器的高背压机组变工况特性研究  

Study on off design characteristics of high back pressure unit coupled with ejector

作　　者：魏德 席新铭[2] 李健[2] 杨志平[2] 戈志华[2] WEI De;XI Xinming;LI Jian;YANG Zhiping;GE Zhihua(GD Power Datong Hudong Generation Co.,Ltd.,Datong 037043,China;National Thermal Power Engineering&Technology Research Center,North China Electric Power University,Beijing 102206,China)

机构地区：[1]国电电力大同湖东发电有限公司,山西大同037043 [2]华北电力大学国家火力发电工程技术研究中心,北京102206

出　　处：《热力发电》2023年第5期107-114,共8页Thermal Power Generation

基　　金：国家重点研发计划项目(2020YFB0606202)。

摘　　要：在喷射器辅助供热的背景下,为了研究喷射器变工况特性,对国内外有关喷射器的计算方法进行调研,建立了喷射器计算模型并将模型与高背压机组进行耦合,得到喷射器变工况时工作蒸汽、引射蒸汽、喷射器背压、喷射器开度对喷射器性能的影响。结果表明:喷射器工作流体压力从0.25 MPa增至0.45 MPa,工作流体质量流量先变大后变小,在工作蒸汽压力为设计工作蒸汽压力时喷射器性能最佳;引射蒸汽压力提高,临界背压提高;引射后的混合流体的压力不仅会影响喷射器的工作,也会影响凝汽器工作;相比抽背机组,高背压耦合喷射器机组低压缸最小冷却流量最大可降低140 t/h,供电范围提高43 MW。Under the background of auxiliary heat supply of ejector,in order to study the characteristics of ejector under variable working conditions,the calculation methods of ejector at home and abroad are investigated,the ejector calculation model is established and coupled with the high back pressure unit.Moreover,the effects of working steam,ejected steam,ejector back pressure,and ejector opening on the performance of the ejector under variable working conditions are obtained.The results show that,when the working fluid pressure of the ejector changes from 0.25 MPa to 0.45 MPa,the mass flow of the working fluid first increases and then decreases,and the ejector has the best performance at the design working steam pressure.The critical back pressure increases with the steam injection pressure.The pressure of the mixed fluid after injection will not only affect the work of the ejector but also the work of the condenser.Compared with the back pumping unit,the minimum cooling flow of the low pressure cylinder of the high back pressure coupling injector unit can be reduced by 140 t/h and the power supply range can be increased by 43 MW.

关 键 词：喷射器 变工况特性 引射比 热电联产 

分 类 号：TM621[电气工程—电力系统及自动化]