Cooling system of a stator assembly for a gas turbine engine having a variable cooling flow mechanism and method of operation

A cooling system integrated into a stator assembly of a gas turbine engine for flowing cooling air toward a downstream rotor assembly, the cooling system comprising:

• an annular nozzle concentric to an engine axis and for flowing cooling air generally toward the rotor assembly;
• a plurality of fixed airfoils circumferentially spaced from one-another and disposed in the nozzle with adjacent fixed airfoils circumferentially defining a plurality of discharge orifices;
• a plurality of pivoting airfoils with each pivoting airfoil disposed in a respective discharge, orifice of the plurality of discharge orifices, wherein each one of the plurality of pivoting airfoils has a leading edge portion projecting outward from a pivoting axis and a trailing edge portion projecting outward from the pivoting axis, and wherein each one of the plurality of pivoting airfoils pivots between a first position and a second position with at least one of the leading and trailing edge portions being closer to respective adjacent fixed airfoils when in the first position as opposed to the second position;
• and
• a sync ring centered to the engine axis and constructed and arranged to move the plurality of pivoting airfoils simultaneously.

A method of operating a cooling system of a gas turbine engine to provide cooling air to a turbine section of the gas turbine engine comprising the steps of:

• moving one or more of a plurality of airfoils disposed in a cooling airflow nozzle into a first position when the gas turbine engine is operating at low rotor speed;
• and
• moving the one or more of the plurality of airfoils into a second position when the gas turbine engine is operating at cruising speed;
• wherein a sync ring centered to the engine axis is constructed and arranged to move the one or more of the plurality of airfoils simultaneously;
• and
• wherein each of the one or more of the plurality of airfoils has a gear in operable contact with a set of teeth of the sync ring.