Fan case rub system
A turbine engine fan case assembly includes a structural case and a liner assembly. A radially accommodating attachment system connects the liner assembly to the structural case. The attachment system comprises a circumferentially-distributed plurality of longitudinally elongate radially outwardly open channels mounted to the liner assembly. The attachment system further comprises an associated plurality of inwardly-projecting tongues mounted to the structural case. Each tongue is accommodated in an associated such channel.
1. A turbine engine fan case assembly comprising:
a structural case;
a liner assembly; and
a radially accommodating attachment system connecting the liner assembly to the structural case and comprising:
a circumferentially-distributed plurality of longitudinally elongate radially outwardly open channels mounted to the liner assembly; and
an associated plurality of inwardly-projecting tongues mounted to the structural case, each tongue accommodated in an associated said channel, wherein:
the tongues are of tongue members each comprising a T-sectioned rail, the arms of the T forming a flange mounted to the structural case, and the leg of the T forming the tongue; and
the channels are each formed by a respective member having, in cross-section, a channel base, a pair of sidewalls extending radially outward from opposite sides of the base and a pair of mounting flanges extending circumferentially outward from radially outboard edges of the sidewalls.
2. The fan case assembly of claim 1 wherein:
each T-sectioned rail is a non-metallic rail; and
each said respective member is a non-metallic member.
3. The fan case assembly of claim 2 wherein:
each non-metallic rail comprises injection molded thermoplastic; and
each non-metallic member comprises injection molded thermoplastic.
4. The fan case assembly of claim 1 wherein:
the channels extend within a honeycomb material.
5. The fan case assembly of claim 1 wherein:
there are 4-10 of said channels and tongues.
6. The fan case assembly of claim 1 wherein:
the channels have a fore-to-aft depth increase.
7. The fan case assembly of claim 1 wherein:
the tongues are a molded or extruded plastic; and
the channels are a molded or extruded plastic.
8. The fan case assembly of claim 1 wherein:
the structural case comprises a non-metallic member principally dictating thermal expansion of the structural case; and
the liner assembly comprises a metallic member principally dictating thermal expansion of the liner assembly.
9. The fan case assembly of claim 8 wherein:
the non-metallic member comprises a carbon fiber member.
10. A turbine engine comprising:
the fan case assembly of claim 1 ; and
a fan, encircled by the fan case.
11. The engine of claim 10 wherein:
the structural case comprises a non-metallic member principally dictating thermal expansion of the structural case;
the liner assembly comprises a metallic member principally dictating thermal expansion of the liner assembly; and
the liner assembly metallic member has a coefficient of thermal expansion within 5% of a coefficient of thermal expansion of blades of the fan.
12. The engine of claim 10 wherein:
the fan has metallic blades;
the structural case comprises a non-metallic member principally dictating thermal expansion of the structural case; and
the liner assembly comprises a metallic member principally dictating thermal expansion of the liner assembly.