GAS TURBINE ENGINE WITH ADAPTIVE TURBINE CLEARANCE CONTROL SYSTEM AND METHOD

A gas turbine engine (20) is provided that includes fan (28), compressor (30), combustion (32), and turbine (34) sections, a fan bypass air path (38), and a turbine active clearance control system (54). The turbine section has a rotor stage (44) and a turbine case clearance control segment (46A). The turbine active clearance control system includes a bleed air mixing system (60), a fan bypass air inlet device (56) configured to receive a fan bypass air flow, and a compressor air bleed structure (58) configured to receive a compressor bleed air flow. The turbine active clearance control system is configurable in a turbine case heating mode in which the bleed air mixing system mixes the fan bypass air flow and the compressor bleed air flow to produce a conditioned air flow that is operable to heat the turbine case clearance control segment.