초록 ▼

A system and method are 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 pr

A system and method are 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.

대표청구항 ▼

1. A cooling air flow control system for a gas turbine having a first cooling air circuit for conducting cooling air from a compressor section to a turbine section for cooling at least one component thereof, said first cooling air circuit being operatively coupled to said compressor section to extra

1. A cooling air flow control system for a gas turbine having a first cooling air circuit for conducting cooling air from a compressor section to a turbine section for cooling at least one component thereof, said first cooling air circuit being operatively coupled to said compressor section to extract said cooling air from a pressure stage of the compressor section that is upstream of a discharge of said compressor section, said cooling air flow control system comprising: a valve for controlling a pressure of cooling air conducted to said component and a controller for controlling said valve in accordance with an operating condition of said turbine.