Environmental Engineering Reference
In-Depth Information
h
z
0
é
ë
r
c
=
(11-24b)
where
dm
=
mass of an incremental length of blade (kg)
r
b
=
average mass density of the blade section (kg/m
3
)
If the force of gravity is considered as deriving from an acceleration in the -Z direction, it
can be treated in a similar manner.
Distributed Loading on the Blade
The combined loading on a HAWT blade caused by aerodynamic forces, shaft rotation,
yaw motion, and gravity are
p
h
=
dA
h
+
m
[(
r
W
2
b
0
+ 2W f
rc
y + f
rs
y)
s
q
p
+
v
W
2
s
q
p
c
q
p
+
e
h
W
2
c
q
p
+
mg
( c
s
q
p
+
c
q
p
s
y - b
0
s
q
p
c
y)
(11-25a)
p
z
=
dA
z
+
m
[- (
r
W
2
b
0
+ 2W f
rc
y + f
rs
y)
c
q
p
+
v
W
2
s
q
p
+
e
h
W
2
s
q
p
c
q
p
-
v
] +
mg
(- c
c
q
p
+
s
q
p
s
y + b
0
c
q
p
c
y)
(11-25b)
p
x
=
m
(
r
W
2
+ 2
v
W
s
q
p
) -
mgc
y
q
h
=
v
W
2
s
q
p
I
hh
(11-25c)
q
z
+ -
mr
W
2
e
h
-
v
W
2
c
q
p
s
q
p
I
hh
+
mge
h
c
y
(11-25d)
q
x
=
q
x ,
a
+ W
2
s
q
p
c
q
p
(
I
z z
-
I
hh
) +
mge
h
s
yq
p
(11-25e)
m
=
ò
r
b
d
h
d
z
(11-25f)
Section
1
m
Section
ò
ò
(11-25g)
e
h
=
r
b
h
d
h
d
z
I
hh
=
ò
ò
r
b
z
2
d
h
d
z
(11-25h)
Section
I
hh
=
ò
r
b
h
2
d
h
d
z
ò
(11-25i)
Section
Search WWH ::
Custom Search