Science. Business. Society.
Vol. 4 (2019), Issue 4, pg(s) 120-123

Exergy analysis of steam turbine governing valve from a super critical thermal power plant

  • 1 Faculty of Engineering, University of Rijeka, Croatia
  • 2 University of Zadar, Maritime Department, Croatia

Abstract

Exergy analysis of steam turbine governing valve from a super critical thermal power plant is presented in this paper. Governing valve was analyzed not only at the highest, but also on two partial steam system loads. The lowest valve exergy destruction is 3598 kW and is obtained at the highest steam system load, while at partial loads of 80% and 60% valve exergy destruction is 13550 kW and 21360 kW. Valve exergy efficiency increases with an increase in system load, from 95.58% at 60% of load to 97.87% at 80% of load. At the highest load, valve exergy efficiency is the highest and is 99.57%. Change in valve steam specific entropy increment (difference in steam specific entropy between valve outlet and inlet) can be used as a tool for quick assessment of valve losses change. The ambient temperature influence on governing valve exergy analysis is low, especially in the highest steam system load where the majority of valve operation can be expected.

Keywords

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