Compressor bleed system for cooling and clearance control

摘要

To improve on thrust specific fuel consumption for a gas turbine engine, compressor bleed for turbine cooling is divided into an air distribution system where at least one duct is valved and the other is continuously flowing restrictively with the excess air passing through the turbine mixing with gas path air in the vicinity of the rotating turbine labyrinth type seal to assure seal cooling with sufficient heating of the rotating parts to achieve minimum gap clearance of the seal.