Design Wind Power Turbine - Hybrid Anisotropic Materials for Wind Power Turbine Blades - page 44

4
3 3

1/2

. e = ( α β - ) [k/ ( λ α β - )] . (2.40)

k

∗ 1/2

Therefore,.the.stress.function.F.includes.the.equation.of.aviation.symmet-
rical.proiles.as.expressed.in.Equation.(2.29).
The.minimum.set.was.determined.from.Equation.(2.38):

. S'(y).=.(y.-.α)(3y.-.2β.-.α).=.0. (2.38)

The.abscissa.of.maximum.is.a.root.of.Equation.(2.38).
Minimizing.the.optimal.number.of.inner.webs.for.two.sections.is.possible.
when.we.analyze.the.shear.stresses..In.Figure 2.21,.we.indicate.the.carbon.
iber.type.on.an.unsupported.leading.edge.
After.simpliication,.the.stress.function.F.from.Equation.(2.29).can.be.given.as:

F(x,y) = Q
8I

1
3a (b - 1 + 4q)] .

.

λ λ

[ x2 - k(y - α )2(y - )] [y + β (2.41)

We.have.determined.the.derivations.of.the.stress.function.F:

∂
∂

F

y = Qx

1
3a (b

1
3a (b - 1 +

{- 2k(y - α )(y - )[y + β - 1 + 4q)] - k(y - α )2 (y + 4q)]

81 λ

. . .

. . (2.42)

- k (y - ) (y - ) + x )

2 2

α β λ

Shear web pultrusion spar

Carbon fiber
in unsupported
leading edge

Fiberglass skin

Shear web pultrusion spar

1/3L

2/3L
Minimize the optimal number of shear webs

FIGURE 2.21
Minimize.the.optimal.number.of.shear.webs..