Compressor turbine wheel

Abstract

A turbine wheel for a gas turbine engine including a compressor impeller and a radial inflow turbine integral to or attached to the compressor impeller is provided. A compressor turbine wheel including features to increase surface area of a surface of the compressor impeller and/or the radial inflow turbine and/or a passage to flow air between the compressor impeller and the radial inflow turbine is further provided. Methods for cooling radial inflow turbines integral to compressor impellers are further provided.

What is claimed is: 
     
         1 . A compressor turbine wheel for a gas turbine engine, the compressor turbine wheel rotatable about a forward-aft axis passing through a forward-aft axial wheel bore at a center of the compressor turbine wheel, the compressor turbine wheel comprising:
 a compressor impeller comprising a forward impeller vane inlet, a radial impeller vane outlet configured to flow compressed air radially outward to a diffuser, an aft inner surface extending from the forward impeller vane inlet to the radial impeller vane outlet, and inner vane side walls projecting forward from the aft inner surface; and   a radial inflow turbine aft of the compressor impeller and comprising a radial turbine vane inlet configured to receive combustion gases from a combustor, an aft turbine vane outlet, a forward inner turbine surface extending from the radial turbine vane inlet to the aft turbine vane outlet, and inner turbine vane side walls projecting aft from the forward inner turbine surface; and   wherein the radial inflow turbine is integral to the compressor impeller.   
     
     
         2 . The compressor turbine wheel of  claim 1 , wherein the aft inner surface and/or the inner vane side walls comprise a rib configured to increase surface area of the aft inner surface and/or the inner vane side walls. 
     
     
         3 . The compressor turbine wheel of  claim 1 , wherein the forward inner turbine surface and/or the inner turbine vane side walls comprise a pin, a rib, a vane, and/or a turbulator configured to increase surface area of the forward inner turbine surface and/or the inner turbine vane side walls. 
     
     
         4 . The compressor turbine wheel of  claim 1 , wherein a passage extends between the aft inner surface and the forward inner turbine surface, the passage configured to provide direct flow of air between the compressor impeller and the radial inflow turbine. 
     
     
         5 . The compressor turbine wheel of  claim 1 , wherein the compressor turbine wheel is configured to cool the radial inflow turbine by conduction from the radial inflow turbine to the compressor impeller. 
     
     
         6 . The compressor turbine wheel of  claim 1 , wherein the compressor turbine wheel is cast, injection molded, three-dimensionally printed, or abrasively machined. 
     
     
         7 . The compressor impeller of  claim 1 , wherein the compressor turbine wheel is metal or ceramic. 
     
     
         8 . A compressor turbine wheel for a gas turbine engine, the compressor turbine wheel rotatable about a forward-aft axis passing through a forward-aft axial wheel bore at a center of the compressor turbine wheel, the compressor turbine wheel comprising:
 a compressor impeller comprising a forward impeller vane inlet, a radial impeller vane outlet configured to flow compressed air radially outward to a diffuser, an aft inner surface extending from the forward impeller vane inlet to the radial impeller vane outlet, and inner vane side walls projecting forward from the aft inner surface; and   a radial inflow turbine aft of the compressor impeller and comprising a radial turbine vane inlet configured to receive combustion gases from a combustor, an aft turbine vane outlet, a forward inner turbine surface extending from the radial turbine vane inlet to the aft turbine vane outlet, and inner turbine vane side walls projecting aft from the forward inner turbine surface;   wherein the radial inflow turbine is integral to the compressor impeller, or an aft outer surface of the compressor impeller is fixed to a forward outer surface of the radial inflow turbine; and   wherein a passage extends between the aft inner surface and the forward inner turbine surface.   
     
     
         9 . The compressor turbine wheel of  claim 8 , wherein the passage is configured to provide cooling air from the compressor impeller to the radial inflow turbine. 
     
     
         10 . The compressor turbine wheel of  claim 8 , wherein the aft inner surface and/or the inner vane side walls comprise a rib configured to increase surface area of the aft inner surface and/or the inner vane side walls. 
     
     
         11 . The compressor turbine wheel of  claim 8 , wherein the forward inner turbine surface and/or the inner turbine vane side walls comprise a pin, a rib, a vane, and/or a turbulator configured to increase surface area of the forward inner turbine surface and/or the inner turbine vane side walls. 
     
     
         12 . The compressor turbine wheel of  claim 8 , wherein a forward outer surface of the radial inflow turbine is brazed or welded to an aft outer surface of the compressor impeller. 
     
     
         13 . The compressor turbine wheel of  claim 8 , wherein two or more passages extend between the aft inner surface and the forward inner turbine surface configured to circulate air between the compressor impeller and the radial inflow turbine. 
     
     
         14 . The compressor turbine wheel of  claim 8 , wherein a second passage extends between the aft inner surface and the forward inner turbine surface;
 wherein the passage is configured to direct flow of air from the compressor impeller to the radial inflow turbine to cool the radial inflow turbine; and   wherein the second passage is configured to return flow of air from the radial inflow turbine to the compressor impeller.   
     
     
         15 . The compressor impeller of  claim 8 , wherein the compressor turbine wheel is metal or ceramic. 
     
     
         16 . A method of cooling a radial inflow turbine of a gas turbine engine rotatable about a forward-aft axis, comprising:
 transferring heat from the radial inflow turbine to a compressor impeller via conduction through the radial inflow turbine and the compressor impeller; and   wherein the radial inflow turbine is integral to the compressor impeller, or an aft outer surface of the compressor impeller is fixed to a forward outer surface of the radial inflow turbine.   
     
     
         17 . The method of  claim 16 , wherein the transferring comprises:
 conducting heat from the radial inflow turbine to the compressor impeller.   
     
     
         18 . The method of  claim 16 , wherein the transferring comprises:
 flowing air aft from the compressor impeller to the radial inflow turbine through a passage between an aft inner surface of the compressor impeller and a forward inner turbine surface of the radial inflow turbine, the aft inner surface extending from a forward impeller vane inlet to a radial impeller vane outlet, the forward inner turbine surface extending from a radial turbine vane inlet to an aft turbine vane outlet.   
     
     
         19 . The method of  claim 16 , wherein the transferring comprises:
 flowing air aft from the compressor impeller to the radial inflow turbine through a passage between an aft inner surface of the compressor impeller and a forward inner turbine surface of the radial inflow turbine, the aft inner surface extending from a forward impeller vane inlet to a radial impeller vane outlet, the forward inner turbine surface extending from a radial turbine vane inlet to an aft turbine vane outlet; and   flowing air forward from the radial inflow turbine to the compressor impeller through a second passage between the aft inner surface and the forward inner turbine surface.   
     
     
         20 . The method of  claim 16 , further comprising:
 increasing turbulence of air flowing through the radial inflow turbine.