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 an active bypass flow control system, controlling bypass of compressed air around one or more seals between a stator and a rotor of a first stage for supplying purging air into a rim cavity. Thus, the flow of compressed air past outer balance seals (12) changes over time as outer balance seal (12) between rim cavity (62) and cooling cavity (25) wears. Active bypass flow control system is designed to control bypass compressed air based upon leakage flow of compressed air flowing past outer balance seal (12) between stator (18) and rotor (20) of a first stage of gas turbine in a gas turbine engine. Active bypass flow control system is an adjustable system in which one or more metering devices can be used (14) to control bypass flow of compressed air. Metering device may include annular ring having at least one metering orifice extending there through, whereby alignment of the metering orifice with the outlet may be adjustable to change a cross-sectional area of an opening of aligned portions of the outlet and the metering orifice.

EFFECT: thus, the wear of the seal is taken into account, as well as the excess leakage flow into the rim cavity, which allows to prevent excess of the total flow of cooling air into the rim cavity.

14 cl, 25 dwg