Plasma sensor stall control system and turbomachinery diagnostics

Abstract

A system for detecting onset of a stall in a rotor is disclosed, the system comprising a plasma sensor spaced radially outwardly and apart from tips of a circumferential row of blades at a location on a static component that is between a first location and a second location wherein the first location is at a first distance of about 25% blade tip-chord length axially forward from the leading edge of a blade and the second location is at a second distance of about 25% blade tip-chord length axially aft from the trailing edge of a blade and wherein the plasma sensor is capable of generating an input signal corresponding to a flow parameter at a location near the tip of a blade and indicative of the onset of a stall and a correlation processor that generates a stability correlation signal.

1 . A system for detecting onset of a stall in a rotor, the system comprising:
 a plasma sensor spaced radially outwardly and apart from tips of a circumferential row of blades at a location on a static component that is between a first location and a second location wherein the first location is at a first distance of about 25% blade tip-chord length axially forward from the leading edge of a blade and the second location is at a second distance of about 25% blade tip-chord length axially aft from the trailing edge of a blade and wherein the plasma sensor is capable of generating an input signal corresponding to a flow parameter at a location near the tip of a blade and indicative of the onset of a stall;   a control system capable of generating a rotor speed signal; and   a correlation processor capable of receiving the input signal and the rotor speed signal wherein the correlation processor generates a stability correlation signal.   
     
     
         2 . A system according to  claim 1  further comprising:
 a plurality of plasma sensors arranged on the static component spaced radially outwardly and apart from tips of the row of blades.   
     
     
         3 . A system according to  claim 1  further comprising:
 a plurality of plasma sensors arranged circumferentially on the static component around an axis of rotation of the rotor and spaced radially outwardly and apart from tips of the row of blades.   
     
     
         4 . A system according to  claim 1  wherein the static component is a casing. 
     
     
         5 . A system according to  claim 4  wherein the plasma sensor is located at a location on the static component corresponding to the mid-chord of a blade. 
     
     
         6 . A system according to  claim 1  wherein the static component is a shroud. 
     
     
         7 . A system according to  claim 1  wherein the rotor comprises a plurality of fan rotors. 
     
     
         8 . A system according to  claim 1  wherein the rotor is a compressor rotor. 
     
     
         9 . A system according to  claim 1  wherein the rotor is a booster rotor. 
     
     
         10 . A system for detecting onset of a stall in a compressor rotor comprising:
 a plasma sensor spaced radially outwardly and apart from tips of a circumferential row of compressor blades at a location on a static component that is between a first location and a second location wherein the first location is at a first distance of about 25% blade tip-chord length axially forward from the leading edge of a blade and the second location is at a second distance of about 25% blade tip-chord length axially aft from the trailing edge of a blade and wherein the plasma sensor is capable of generating an input signal indicative of the onset of a stall in the compressor; and   a correlation processor capable of receiving the input signal and a rotor speed signal wherein the correlation processor generates a stability correlation signal.   
     
     
         11 . A system according to  claim 10  further comprising a plurality of compressor rotors wherein a plurality plasma sensors are located on the static component surrounding tips of compressor blades of at least two compressor rotors. 
     
     
         12 . A system according to  claim 10  further comprising a plurality of plasma sensors arranged circumferentially on the static component around an axis of rotation of the compressor rotor and spaced radially outwardly and apart from tips of the row of compressor blades. 
     
     
         13 . A system for controlling an operating tip clearance between a rotor and a static component, the system comprising:
 a plasma sensor spaced radially outwardly and apart from tips of a circumferential row of blades at a location on a static component wherein the plasma sensor is capable of generating an input signal corresponding to a flow parameter at a location near the tip of a blade;   a correlation processor capable of generating a correlation signal indicative of the operating tip clearance based on the input signal; and   a control system capable of controlling the operating tip clearance based on the correlation signal.   
     
     
         14 . A system according to  claim 13  wherein the plasma sensor is located on the static component between a first location and a second location wherein the first location is at a first distance of about 25% blade tip-chord length axially forward from the leading edge of a blade and the second location is at a second distance of about 25% blade tip-chord length axially aft from the trailing edge of a blade. 
     
     
         15 . A system according to  claim 13  wherein the plasma sensor is located at a location on the static component corresponding to the mid-chord of a blade. 
     
     
         16 . A system according to  claim 13  further comprising:
 a plurality of plasma sensors arranged circumferentially on the static component around an axis of rotation of the rotor and spaced radially outwardly and apart from tips of the row of blades.   
     
     
         17 . A system according to  claim 13  wherein the static component is a casing. 
     
     
         18 . A system according to  claim 13  wherein the static component is a shroud. 
     
     
         19 . A system according to  claim 13  wherein the rotor is a turbine rotor. 
     
     
         20 . A system according to  claim 13  wherein the rotor is a compressor rotor.