Turbine airfoil serpentine flow circuit with a built-in pressure regulator

Abstract

An airfoil for used in a gas turbine engine, the airfoil having a serpentine cooling flow circuit formed within the airfoil to provide cooling for the leading edge and trailing edge of the airfoil. A first leg of the serpentine circuit supplies cooling air to a leading edge cooling channel and a showerhead arrangement. A second and third leg of the serpentine circuit carries cooling air not bled off to the leading edge toward the trailing edge of the airfoil for cooling. Located between the second leg and the third leg is a cavity in which cooling air flows. A convergent nozzle is formed on the second leg opening into the cavity, with a divergent nozzle formed on the third leg also opening into the cavity. The two nozzles provide a way to regulate the flow rate through the serpentine circuit in order that a higher pressure is available for the leading edge cooling, and a lower pressure is available for the trailing edge cooling. Also, the nozzles are located in the cavity such that a tool can be inserted into the cavity to change the nozzle size, and therefore regulate the flow rate and pressures within the serpentine cooling flow circuit.

Dependencies are inferred from the claim text.