The Influence of Overlap Degree Research on Nozzle Governing Characteristic

Lin Ma, Jian-qun Xu, Xue-yu Dong, Tao Yang

Electrical Power Simulation and Control Engineering Center of Nanjing Institute of Technology, Nanjing, China.
School of Energy and Environment, Southeast University, Nanjing, China.

DOI: 10.4236/epe.2013.54B124                

Abstract

To solve the problems existing in the flow characteristics of steam turbine unit, the influence of valve overlap degree on nozzle governing steam turbine had been studied. The combined flow characteristics of given valve overlap degree were obtained for a 600MW steam turbine unit by the method of theoretical calculation combined with simulation test, and the influence of valve overlap degree on governing stage efficiency and steam chest pressure had been also analyzed. This paper discussed the selection of rational overlap degree and introduced a new method of building model for governing stage efficiency of steam turbine in constant pressure operation condition, which provided theoretical guidance for optimization research on nozzle governing steam turbine operation.

Keywords

Overlap Degree; Flow Characteristics; Valve Point; Governing Stage Efficiency; Operation Mode

Conflicts of Interest

The authors declare no conflicts of interest.

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