Cooling air supply arrangement for a gas turbine engine

Claim 1

An improved gas turbine engine comprising a rotor, a source of cooling air at a high supply pressure, a cooling air supply arrangement for delivering cooling air from said source to said rotor, said cooling air supply arrangement including a first passage for supplying a first flow of said cooling air from said source to a first area of said rotor to be cooled, said first flow being at a first pressure lower than said high supply pressure, a second passage for supplying a second flow of said cooling air to a second area of said rotor, said second flow being at a reduced second pressure lower than said first pressure, and sealing means between said first area and said second area for resisting flow of cooling air at said first pressure from said first area to said second area, wherein the improvement comprises a part of said second passage being incorporated into said sealing means, said part of said second passage including nozzles provided in said second passage and oriented in a direction to discharge at least part of said second flow of cooling air in an upstream direction directly against leakage flow in said sealing means from said first area toward said second area to reduce such leakage flow and to simultaneously reduce pressure of said second flow of cooling air to said second area.