Patent ID: 9593590
Date: 2017-03-14
CPC Classifications: F01D,F05D

Claim:
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, 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; and further comprising a position control system for controlling a position of the at least one metering device relative to the outlet of the at least one bypass channel, wherein the position control system further comprises at least one sensor configured to measure an amount of leakage flow occurring across the at least one metering device, wherein the metering device is adjusted to exhaust less compressed air from the outlet in response to data derived from the at least one sensor indicating wearing of the outer balance seal.