Turbomachine and method of assembly
A turbomachine includes an annular casing and a fan disposed inside the annular casing and mounted for rotation about an axial centerline. The fan includes fan blades that extend radially outwardly toward the annular casing. The fan has an average chord fan width according to a first performance factor. The fan has a quantity of fan blades according to a second performance factor.
1 . A turbomachine for an aircraft comprising:
an annular casing; and
a fan disposed inside the annular casing and mounted for rotation about an axial centerline, the fan including fan blades that extend radially outwardly toward the annular casing;
wherein the fan includes an average fan chord width of the fan blades (“c”), a diameter of the fan (“D”), a fan pressure ratio (“FPR”), and a redline corrected fan tip Mach number (“M tip,c (RL) ”) according to a First Performance Factor (“FPF”),
wherein
FPF
=
[
c
0.15
·
D
]
/
[
[
F
P
R
-
1
0.4
]
/
M
tip
,
c
(
R
L
)
]
-
1.23
,
wherein
m
1
·
[
M
tip
,
c
(
RL
)
-
1.1
]
+
6
>
FPF
>
m
1
·
[
M
tip
,
c
(
RL
)
-
1.1
]
+
Δ
y
1
,
and
wherein 0<Δy 1 <6;
wherein the fan includes a fan hub-to-tip ratio (“HTR”), a fan blade count (“BC”), FPR, and M tip,c (RL) according to a Second Performance Factor (“SPF”),
wherein
SPF
=
π
4
(
1
-
HTR
2
)
/
(
BC
20
)
/
(
FPR
-
1
0.4
)
/
M
tip
,
c
(
RL
)
-
0.97
,
wherein
m
2
·
[
M
t
ip
,
c
(
R
L
)
-
1
.
1
]
+
1.5
>
SPF
>
m
2
·
[
M
t
ip
,
c
(
R
L
)
-
1
.
1
]
+
Δ
y
2
,
and
wherein 0<Δy 2 <1.5.
2 . The turbomachine of claim 1 , wherein M tip,c (RL) is within a range equal to or greater than 0.45 and equal to or less than 1.34.
3 . The turbomachine of claim 1 , wherein m 1 is equal to 0.87 when M tip,c (RL) is greater than or equal to 1.1.
4 . The turbomachine of claim 1 , wherein m 1 is equal to 3.34 when M tip,c (RL) is less than 1.1.
5 . The turbomachine of claim 1 , wherein Δy 1 is equal to or greater than 0.0125 and less than 6.
6 . The turbomachine of claim 1 , wherein Δy 1 is equal to or greater than 0.04 and less than 6.
7 . The turbomachine of claim 1 , wherein Δy 1 is equal to or greater than 0.07 and less than 6.
8 . The turbomachine of claim 1 , wherein Δy 1 is equal to or greater than 0.1 and less than 6.
9 . The turbomachine of claim 1 , wherein the turbomachine has a gear ratio within a range equal to or greater than 3.2 and equal to or less than 5.0.
10 . The turbomachine of claim 1 , wherein the fan blade includes an airfoil portion made from a polymer matrix composite (PMC) material, a metallic leading edge, a ratio c/D is between 0.16 and 0.21, and the fan has between 16 and 25 fan blades.
11 . The turbomachine of claim 1 , wherein a ratio c/D is within a range equal to or greater than 0.1 and equal to or less than 0.3.
12 . The turbomachine of claim 1 , wherein FPR is within a range equal to or greater than 1.2 and equal to or less than 1.5.
13 . The turbomachine of claim 1 , wherein m 2 is equal to 0.41 when M tip,c (RL) is greater than or equal to 1.1.
14 . The turbomachine of claim 1 , wherein m 2 is equal to 0.55 when M tip,c (RL) is less than 1.1.
15 . The turbomachine of claim 1 , wherein Δy 2 is equal to or greater than 0.0075 and less than 1.5.
16 . The turbomachine of claim 1 , wherein Δy 2 is equal to or greater than 0.02 and less than 1.5.
17 . The turbomachine of claim 1 , wherein Δy 2 is equal to or greater than 0.04 and less than 1.5.
18 . The turbomachine of claim 1 , wherein Δy 2 is equal to or greater than 0.06 and less than 1.5.
19 . The turbomachine of claim 1 , wherein HTR is within a range equal to or greater than 0.1 and equal to or less than 0.5.
20 . The turbomachine of claim 1 , wherein BC is within a range equal to or greater than 10 and equal to or less than 18.