Method for pressure modulation of turbine sidewall cavities

Patent · Tue Jan 01 00:00:00 EST 2002

OSTI ID:874417

Leone, Sal Albert ^[1]; Book, Matthew David ^[2]; Banares, Christopher R ^[3]

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1. Scotia, NY
2. Altamont, NY
3. Schenectady, NY

A method is provided for controlling cooling air flow for pressure modulation of turbine components, such as the turbine outer sidewall cavities. The pressure at which cooling and purge air is supplied to the turbine outer side wall cavities is modulated, based on compressor discharge pressure (Pcd), thereby to generally maintain the back flow margin (BFM) so as to minimize excessive leakage and the consequent performance deterioration. In an exemplary embodiment, the air pressure within the third stage outer side wall cavity and the air pressure within the fourth stage outer side wall cavity are each controlled to a respective value that is a respective prescribed percentage of the concurrent compressor discharge pressure. The prescribed percentage may be determined from a ratio of the respective outer side wall pressure to compressor discharge pressure at Cold Day Turn Down (CDTD) required to provide a prescribed back flow margin.

• Research Organization: General Electric Co., Schenectady, NY (United States)
• DOE Contract Number: FC21-95MC31176
• Assignee: General Electric Company (Schenectady, NY)
• Patent Number(s): US 6385958
• OSTI ID: 874417
• Country of Publication: United States
• Language: English

Related Subjects

method
pressure
modulation
turbine
sidewall
cavities
provided
controlling
cooling
air
flow
components
outer
purge
supplied
wall
modulated
based
compressor
discharge
pcd
maintain
margin
bfm
minimize
excessive
leakage
consequent
performance
deterioration
exemplary
embodiment
third
stage
cavity
fourth
controlled
value
prescribed
percentage
concurrent
determined
ratio
cold
cdtd
required
provide
air flow
compressor discharge
turbine component
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