Patent ID: 7785063

Claim:
A blade clearance control system for a turbine engine having a compressor section, a rotor assembly with a rotor, and an exhaust duct, the system comprising: a blade ring concentric with the rotor assembly and positioned radially outward from blade tips of the rotor assembly to define a gap therebetween; a first cooling circuit in fluid communication with the compressor section and the rotor, the first cooling circuit being in thermal communication with a heat exchanger; and a first heating circuit in fluid communication with the exhaust duct and the blade ring, wherein during engine start up the first cooling circuit extracts compressor delivery air from the compressor section, cools the compressor delivery air via the heat exchanger and supplies the compressor delivery air to the rotor for cooling of the rotor, and wherein during engine start up the first heating circuit extracts hot exhaust gases from the exhaust duct and supplies the hot exhaust gases to the blade ring for heating of the blade ring.