Method of operating a heated guide vane assembly

Abstract

A method of operating a heated guide vane assembly for turbomachinery, the heated guide vane assembly including a plurality of guide vanes each having two major surfaces joined about their periphery by edges and an associated electric heater element secured to at least one major surface of the guide vanes. The method includes the steps of energizing heater elements on at least one of the guide vanes, de-energizing heater elements on at least one of the guide vanes, and energizing heater elements on at least one of the guide vanes which was not energized in the first energizing step.

1 . A method of operating a heated guide vane assembly for turbomachinery, said heated guide vane assembly including a plurality of guide vanes each having two major surfaces joined about their periphery by edges and an associated electric heater element secured to at least one major surface thereof, said method comprising the steps of:
 energizing heater elements on at least one of said guide vanes;   de-energizing heater elements on at least one of said guide vanes; and   energizing heater elements on at least one of said guide vanes which was not energized in said first energizing step.   
     
     
         2 . A method of operating a heated guide vane assembly for turbomachinery in accordance with  claim 1 , wherein each of said energizing steps includes energizing multiple heater elements. 
     
     
         3 . A method of operating a heated guide vane assembly for turbomachinery in accordance with  claim 2 , wherein said multiple heater elements are secured to multiple guide vanes. 
     
     
         4 . A method of operating a heated guide vane assembly for turbomachinery in accordance with  claim 1 , wherein said energizing and de-energizing steps are repeated on a continuous basis. 
     
     
         5 . A method of operating a heated guide vane assembly for turbomachinery in accordance with  claim 1 , wherein said energizing steps are sustained for a shorter time period than said de-energizing steps for a specific heater element. 
     
     
         6 . A method of operating a heated guide vane assembly for turbomachinery in accordance with  claim 1 , further comprising a step of energizing a heater element on another structure. 
     
     
         7 . A method of operating a heated guide vane assembly for turbomachinery in accordance with  claim 1 , wherein each energizing step has similar power requirements. 
     
     
         8 . A method of operating a heated guide vane assembly for turbomachinery in accordance with  claim 1 , said assembly further including a control system to selectively energize and de-energize said heater elements. 
     
     
         9 . A method of operating a heated guide vane assembly for turbomachinery in accordance with  claim 8 , wherein said control system is operable to selectively energize a plurality of heater elements symmetrically arranged around a centerline of said turbomachinery and selectively de-energize said plurality of heater elements sequentially in a pattern which advances around said centerline. 
     
     
         10 . A method of operating a heated guide vane assembly for a gas turbine engine, said heated guide vane assembly including a plurality of guide vanes each having two major surfaces joined about their periphery by edges and an associated electric heater element secured to at least one major surface thereof, said method comprising the steps of:
 energizing heater elements on a plurality of said guide vanes;   de-energizing heater elements on said plurality said guide vanes;   energizing heater elements on a plurality of said guide vanes which was not energized in said first energizing step; and   repeating said energizing and de-energizing steps on a continuous basis.