ACTIVE BYPASS FLOW CONTROL FOR A SEAL IN A GAS TURBINE ENGINE

摘要

An active bypass flow control system for controlling bypass compressed air based upon leakage flow of compressed air flowing past an outer balance seal between a stator and rotor of a first stage of a gas turbine in a gas turbine engine is disclosed. The active bypass flow control system is an adjustable system in which one or more metering devices may be used to control the flow of bypass compressed air as the flow of compressed air past the outer balance seal changes over time as the outer balance seal between the rim cavity and the cooling cavity wears In at least one embodiment, the metering device may include an annular ring having at least one metering orifice extending therethrough, 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

主权项

1. An active bypass flow control system for an outer balance seal, comprising:
a stator assembly positioned in proximity to a first stage rotor whereby a compressed air channel is positioned between a portion of the stator assembly and a rotor shaft, at least one outer balance seal configured to at least reduce a portion of hot gases from flowing into a cooling cavity, at least one bypass channel extending from an inlet in fluid communication with the compressed air channel upstream of the at least one outer balance seal to an outlet in fluid communication with the compressed air channel downstream from the at least one outer balance seal, and at least one metering device that is adjustable to adjust the flow of cooling fluids through the at least one bypass channel to accommodate a changing flow of compressed air past the at least one outer balance seal as the outer balance seal wears during turbine engine operation