A method and system for providing a cooling flow from a compressor to a turbine in a gas turbine engine. First, second and third cooling air flows are provided from the compressor through respective ejectors as external bleed air flows to stages of the turbine. A first ejector combines a first bleed air flow extracted from the compressor with a lower pressure air flow extracted from the compressor to form the first cooling air flow. A second ejector combines a second bleed air flow extracted from the compressor with a secondary portion extracted from the first bleed air flow to form the second cooling air flow. A third ejector combines a third bleed air flow extracted from the compressor with a secondary portion extracted from the second bleed air flow to form the third cooling air flow.
STATEMENT REGARDING FEDERALLY SPONSORED DEVELOPMENT
[0001] Development for this invention was supported in part by Contract No. DE-FC26-05NT42644, awarded by the United States Department of Energy. Accordingly, the United States Government may have certain rights in this invention.