ACTIVE BYPASS FLOW CONTROL FOR SEAL IN GAS TURBINE ENGINE Russian patent published in 2018 - IPC F01D11/06 F01D5/08 

FIELD: gas turbine engines.

SUBSTANCE: invention relates generally to gas turbine engines, and more particularly to a system for actively controlling the bypass flow of compressed air around one or more seals between a stator and a rotor assembly of the first stage for supplying purging air into a rim cavity. Flow of compressed air through outer balance seal (12) in compressed air channel (16) changes over time as outer balance seal (12) between stator (18) and rotor (20) wears. Active bypass flow control system is designed for controlling bypass of compressed air based upon leakage flow of compressed air flowing through outer balance seal (12) between stator (18) and rotor (20) of a first stage of gas turbine (21) in a gas turbine engine. Active bypass flow control system is a controlled system in which one or more metering devices (14) can be used to control the bypass flow of compressed air. Furthermore, metering device (14) may include valve (70) formed from one or more pins (72) movable between open and closed positions. Pin (72) at least partially bisects bypass channel (28) to regulate flow.

EFFECT: invention takes into account the wear of the seal and additional leakage flow into the rim cavity, which allows to prevent excessive total flow of cooling air into the rim cavity.

10 cl, 25 dwg