Liner for gas turbine engine

Abstract

An embodiment of a gas turbine engine having a liner and casing is disclosed. The liner is disposed between the casing and a rotatable turbomachinery component. In one form, the rotatable turbomachinery component is a turbofan engine. The liner can be thin relative to a distance between the liner and the casing. Protrusions can be used between the liner and the casing. The protrusions can be a rib and can extend from the casing or the liner. An insert, such as an abradable surface, can be used with the liner. A filler can be used in the space between the liner and the casing.

What is claimed is: 
     
         1 . An apparatus comprising:
 a gas turbine engine having a casing and a flow path located radially inward of the casing within which is disposed a rotatable turbomachinery component, the flow path bounded by a construction that provides a liner surface located between the rotatable turbomachinery component and the casing, the construction having a base thickness between a flow path side and a non-flow path side which is smaller than an offset between the construction and the casing, the offset being free of the construction;   wherein the construction that provides the liner surface forms a flow path surface during a nominal mode of operation of the rotatable turbomachinery component, and wherein the construction that provides the liner surface is constructed to be sacrificial during an off-nominal mode of operation of the rotatable turbomachinery component such that a portion of the turbomachinery component can penetrate into an area free from the construction.   
     
     
         2 . The apparatus of  claim 1 , wherein the rotatable turbomachinery component is a fan, and wherein an annular liner is formed that is constructed from a plurality of construction segments, and wherein the construction that provides the liner surface is a single article that forms the flow path surface and is substantially free of internal voids. 
     
     
         3 . The apparatus of  claim 1 , wherein the construction includes a base portion and an abradable material adjacent the base portion. 
     
     
         4 . The apparatus of  claim 1 , wherein the off-nominal mode of operation includes an orbiting motion of the turbomachinery component, and wherein the gas turbine engine also includes protrusions disposed in the area free from the construction. 
     
     
         5 . The apparatus of  claim 4 , wherein the construction that provides the liner surface includes the protrusions. 
     
     
         6 . The apparatus of  claim 1 , wherein the area free from the construction includes a low density filler material. 
     
     
         7 . The apparatus of  claim 1 , wherein the construction includes a plurality of materials. 
     
     
         8 . An apparatus comprising:
 a gas turbine engine including a fan section having a rotatable fan blade portion structured to change a pressure of a working fluid flowing through a flow path of the fan section;   a casing radially outward of the rotatable fan blade portion and having a shape that diverges from the flow path of the fan section; and   a component having a liner surface radially inward from the casing to separate the casing from the rotatable fan blade portion, the component offset from the casing to create a space free of a honeycomb structure intermediate the liner and the casing, the space being larger than a thickness of the component axially coincident with the rotatable fan blade portion.   
     
     
         9 . The apparatus of  claim 8 , wherein the component is fixed relative to the casing through one of mechanical fastening or being bonded in place. 
     
     
         10 . The apparatus of  claim 8 , wherein a coupling interface between the component and the casing is structured to fail and release the component when the fan blade portion contacts the component. 
     
     
         11 . The apparatus of  claim 8 , wherein the component is stamped sheet metal. 
     
     
         12 . The apparatus of  claim 8 , wherein the component is molded, and wherein the component is one of plastic and composite. 
     
     
         13 . The apparatus of  claim 8 , wherein the component includes a solidity that substantially lacks internal voids. 
     
     
         14 . The apparatus of  claim 8 , wherein the liner includes a base plate and which further includes elongate portions that extend from between a back of the component and the casing. 
     
     
         15 . The apparatus of  claim 8 , wherein the space free of a honeycomb structure is an empty space. 
     
     
         16 . The apparatus of  claim 8  further comprising a compressor rotatingly coupled with a turbine and wherein the casing is configured to enclose the fan blade; and
 reaction means for ingressing a portion of the fan blade into a space formed between the casing and the reaction means, the reaction means disposed between the casing and the fan blade to create a non-flow path volume, the reaction means having a predominate thickness extending between an upstream end and a downstream end, the non-flow path volume having a depth measured between the casing to the predominate thickness, and wherein the thickness of the reaction means is substantially smaller than the depth measured between the casing and the predominate thickness. 
 
     
     
         17 . A method comprising:
 rotating a bladed member of a gas turbine engine having a casing and a liner situated between the casing and the bladed member to create an area therebetween, the bladed member travelling along a nominal arc of rotation;   impacting at least a portion of the bladed member with a liner located between the bladed member and a casing of the gas turbine engine; and   reacting the liner with the portion of the bladed member to expose a volume formed by a placement of the liner relative to the casing, the liner providing an offset flow path surface for a working fluid from the casing.   
     
     
         18 . The method of  claim 17 , which further includes penetrating the liner with the portion of the bladed member. 
     
     
         19 . The method of  claim 17 , wherein the reacting includes breaking the liner, and wherein the breaking includes removing at least a portion of the liner. 
     
     
         20 . The method of  claim 19  wherein the removing includes breaching a manner in which the liner is affixed relative to the casing, and wherein the breaching includes destroying a bond between the liner and the casing.