Gas turbine metering valve

Abstract

A metering valve for industrial gas turbine engines includes a valve body, a flow tube, an orifice plate, a central flow body, and a mover. The valve body has an inlet and an outlet. The flow tube is carried for axial movement in slidable and sealing engagement with the valve body at an inlet end and an outlet end. The orifice plate has an outlet. The central flow body is provided on an upstream end of the orifice plate and has an annular seal configured to seat into engagement with the outlet end of the flow tube when the flow tube is moved to a downstream position. The central flow body also includes a central, protruding flow diverter upstream and central of the annular seal. The mover is provided in the valve body and is configured to carry the flow tube for displacement of the output end toward and away from the central flow body.

The invention claimed is:  
     
         1 . A metering valve for industrial gas turbine engines, comprising: 
 a valve body having an inlet and an outlet;    a flow tube carried for axial movement in slidable and sealing engagement with the valve body at an inlet end and an outlet end;    an orifice plate having an outlet;    a central flow body provided on an upstream end of the orifice plate having an annular seal configured to seat into engagement with the outlet end of the flow tube when the flow tube is moved to a downstream position and a central, protruding flow diverter upstream and central of the annular seal; and    a mover provided in the valve body and configured to carry the flow tube for displacement of the output end toward and away from the central flow body.    
     
     
         2 . The valve of  claim 1  wherein the mover comprises an armature carried by the flow tube and a solenoid provided about the armature and electrically communicating with the armature to move the armature and the flow tube to selected axial positions.  
     
     
         3 . The valve of  claim 1  wherein the annular seal comprises a circumferential seal.  
     
     
         4 . The valve of  claim 1  wherein the flow diverter of the orifice plate comprises a convex, leading end nipple.  
     
     
         5 . The valve of  claim 4  wherein the flow diverter further comprises a concave lip extending circumferentially about the convex nipple.  
     
     
         6 . The valve of  claim 1  wherein the flow diverter comprises a central flow diverter with a hemispherical head.  
     
     
         7 . The valve of  claim 6  wherein the orifice plate comprises an outer mounting ring, the flow body, and a spider carrying the flow body coaxially within the mounting ring.  
     
     
         8 . The valve of  claim 7  wherein the orifice plate further comprises a circumferential array of flow apertures provided between adjacent arms of the spider and about the circumferential seal.  
     
     
         9 . The valve body of  claim 1  wherein the flow diverter comprises a Rankine half-body of revolution.  
     
     
         10 . The valve body of  claim 9  wherein the flow diverter is removably mounted to the upstream end of the orifice plate with a fastener.  
     
     
         11 . A gas turbine metering valve, comprising: 
 a valve body having an inlet and an outlet;    a flow tube carried for axial movement in sliding and sealing engagement at an inlet end with the body inlet and at an outlet end with the body outlet;    a central flow body having a circumferential seal configured to seat in engagement with the output end of the flow tube;    a mover provided in the valve body and configured to carry the flow tube for axial movement to position the output end toward and away from the central flow body to adjust flow capacity through the valve; and    a displacement sensor configured to detect axial positioning of the flow tube relative to the central flow body.    
     
     
         12 . The valve of  claim 11  wherein the central flow body comprises an orifice plate, the flow tube is a cylindrical tube, and the flow body extends in an upstream direction from the orifice plate in axial alignment with the flow tube to mate and demate with the output end of the flow tube as the flow tube is moved in upstream and downstream directions, respectively.  
     
     
         13 . The valve of  claim 11  wherein the central flow body cooperates with the output end of the flow tube, when in spaced-apart relation, to provide a flow passage therebetween, wherein volumetric flow capacity of the valve is adjusted by moving the flow tube to a desired position relative to the flow body to impart a corresponding volumetric flow capacity there between.  
     
     
         14 . The valve of  claim 11  wherein the displacement sensor comprises a linear variable differential transformer (LVDT).  
     
     
         15 . The valve of  claim 11  wherein the linear variable differential transformer is affixed at a first end to the valve body and is affixed at a second end to the flow tube.  
     
     
         16 . The valve of  claim 11  wherein the central flow body is removably secured in the valve body at the body outlet.  
     
     
         17 . The valve of  claim 11  further comprising a spring interposed between the valve body and the flow tube to bias the flow tube at the downstream end for engagement with the flow body.  
     
     
         18 . The valve of  claim 17  wherein the mover comprises a linear motor with an armature affixed to the flow tube, a pole piece, and wire windings.  
     
     
         19 . The valve of  claim 18  wherein the wire windings are energized to generate magnetic forces that attract the armature to move the flow tube upstream and compress the spring.  
     
     
         20 . The valve of  claim 19  further comprising processing circuitry configured to control energizing of the wire windings to realize a desired upstream positioning of the flow tube relative to the central flow body to achieve a desired flow rate through the valve body.