Dynamic Strength - Hybrid Anisotropic Materials for Wind Power Turbine Blades - page 137

Z

dF
rdθ Fz

Mz

L.E. T.E.

My

A

A c Fy

y

x

Section A-A

ez e45
eyθ

Y

Mx

X

Power turbine blade with resistance strain gauges

FIGURE 5.2
A.power.wind.turbine.blade.with.resistance.strain.gauges..(From.Bronsted,.Lithoit,.and.Lystrup..
2005.. Composite materials for wind power turbine blades .. Copenhagen:. Technical. University. of.
Denmark,.Riso.National.Laboratory.for.Sustainable.Energy..With.permission.)

where:
.E xy ,.E xz .are.the.modulus.of.normal.elasticity.in.x,.z.directions;
.G xy ,.G xz .are.the.modulus.of.shear.elasticity.in.x,.z.directions.
.α.is.a.distance.from.end.of.proile.to.center;
.β.is.a.distance.from.center.to.end.of.proile.

5.7 MechanicalandThermalProperties

5.7.1 Introduction

One. of. the. most. important. characteristics. of. all. prepregs. is. the. way. the.
material. behaves. when. acting. with. mechanical. and. thermal. loads.. With.
temperature. changes. from. -20°C. to. +40°C,. this. mechanical. and. thermal.
data.is.critical.to.almost.every.application.including.power.turbine.blades..
Although.an.accurate.determination.as.to.whether.it.is.suitable.for.use.at.a.
particular.temperature.can.only.be.made.by.testing.the.product.in.the.load-
ing.coniguration.that.it.will.see.in.service,.the.data.presented.here.can.be.
used.as.a.guide.for.initial.product.selection.