US 11,702,945 B2
Turbine engine fan case with tip injection air recirculation passage
Robert W. Heeter, Noblesville, IN (US); and Daniel E. Molnar, Jr., Lebanon, IN (US)
Assigned to Rolls-Royce North American Technologies Inc., Indianapolis, IN (US)
Filed by Rolls-Royce North American Technologies Inc., Indianapolis, IN (US)
Filed on Dec. 22, 2021, as Appl. No. 17/560,227.
Prior Publication US 2023/0193771 A1, Jun. 22, 2023
Int. Cl. F01D 25/26 (2006.01); F01D 9/06 (2006.01)
CPC F01D 9/06 (2013.01) [F01D 25/26 (2013.01); F05D 2220/32 (2013.01); F05D 2230/60 (2013.01); F05D 2240/12 (2013.01); F05D 2240/14 (2013.01); F05D 2260/60 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A fan case assembly adapted for use with a gas turbine engine,
the fan case assembly comprising
a fan track liner that extends circumferentially at least partway about a central axis of the gas turbine engine, the fan track liner including a forward end, an aft end spaced apart axially from the forward end, and an inner radial surface that extends between the forward end and the aft end to define a gas path of the gas turbine engine,
an annular case configured to support the fan track liner at a radial position relative to the central axis, the annular case including an outer wall that extends circumferentially around the central axis of the gas turbine engine and a hook that extends radially inward from the outer wall to support the forward end of the fan track liner, the outer wall including an outer radial surface, and
a discrete air recirculation duct configured to direct a portion of gases flowing through the gas path of the gas turbine engine from the aft end of the fan track liner into the gas path axially forward of the forward end of the fan track liner, the air recirculation duct including
an extraction port in fluid communication with the gas path of the gas turbine engine that extends radially through the entire outer wall at a location axially aft of the aft end of the fan track liner,
a conduit in fluid communication with the extraction port, the conduit extends axially forward from the extraction port toward the forward end of the fan track liner, the conduit located radially outward of the outer wall such that the gases flowing through the conduit are not exposed to the outer radial surface of the outer wall, and
an injection port in fluid communication with the gas path of the gas turbine engine and the conduit, the injection port extends radially inward from the conduit through the entire outer wall at a location axially forward of the forward end of the fan track liner and the hook of the annular case.