COOLING PASSAGES FOR A MID-TURBINE FRAME

摘要

A mid-turbine frame assembly (57) of a gas turbine engine includes an outer frame case (62) and an inner frame case (64) which includes a first plurality of cooling holes (110A) and a second plurality of flow balancing cooling holes (156). A plurality of tie rods (90A) is circumferentially spaced around the inner frame case and includes an inlet passage (118) that is aligned with the first plurality of cooling holes. A first plurality of hollow airfoils (59) surrounds the tie rods and a third plurality of hollow airfoils (59) is aligned with the second plurality of cooling holes. A method of cooling the hollow airfoils comprises directing the cooling airflow through the first and second plurality of cooling holes.