凝汽式汽轮机级组当量喷嘴通流面积计算方法及其应用

Flow Passage Area Calculation of Stage Group Equivalent Nozzle and Its Application in Condensing Steam Turbine

针对汽轮机通流部分故障,总结了现有的诊断方法,指出其中存在的不足,并提出基于当量喷嘴通流面积的汽轮机通流部分故障诊断方法。对汽轮机由额定负荷降低到50%负荷时级组当量喷嘴通流面积的偏差率进行计算分析,结果表明:在汽轮机通流部分状态正常的情况下,当量喷嘴通流面积随负荷变化很小,可以准确表征级组的通流面积大小。最后分别以两台300MW汽轮机为例,将运行中在线监测计算得到的各级组当量喷嘴通流面积与其正常值进行对比,对汽轮机通流部分状况进行了诊断。

Aiming at the failure in flow passages of the steam turbine,the diagnosis methods in service were summarized and their shortcomings were stated; basing on equivalent nozzle flow passage area,a new fault diagnosis method was proposed.When reducing steam turbine＇ s rated load to 50％,having deviation rate of the equivalent nozzle flow passage area analyzed to show that,when the steam turbine＇s flow passage works normally,the equivalent nozzle flow passage area changes little with the variation of the load,it can represent the changes of the stage group＇ s flow passage area.Taking two sets of 300 MW steam turbines as the example,diagnosing and comparing their equivalent nozzle flow passage areas monitored online with their normal values was implemented,including the through-flow of the steam turbine.