Patent · US Expired

Steam turbine nozzle trailing edge modification for improved stage performance

US6109869A · kind A · utility

16Cited by
2References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 13, 1998
Grant dateAug 29, 2000
Priority date
Expiry dateAug 13, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49325
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

In a reverse design for partitions of a steam turbine having decreased throat dimension therebetween with increased radial height, the trailing edges are set back from approximately mid-span to a tip of the partition to increase the throat dimension with radial height relative to the prior reverse design configuration. Secondary vortices adjacent the radial inner and outer end walls are maintained separated from on another by the design, thereby minimizing or eliminating aerodynamic losses from interactive secondary flow effects while improving flow distribution at the bucket entrance and stage exit. In a further embodiment, a free vortex design having increasing throat dimension from the hub to the tip may be modified to further increase the throat dimension from the hub to approximately the mid-span by providing setbacks along the trailing edge of the partition between the hub and mid-span. The setbacks can be provided as original equipment or retrofitted in the field by cutting and removing trailing edge portions.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.