Problem Description#

The goal is to design the composite structure of a rotor blade to match some desired beam properties.

Scope of the study#

This example assumes a uniform design along the span of the blade. A specific topology which is a box spar design is considered for the structure, as shown in Fig. 2. More details about the parameterization of the structure can be found in Section: Cross-sectional Parameterization and Beam Properties.


Figure 2 Topology of the cross-section.#


Airfoil, chord length and target beam properties are summarized in Table 3.

Table 3 Specifications#



Chord length

\(20.76\ \mathrm{in}\)

Mass per unit length (\(\hat{m}\))

\(0.00149\ \mathrm{lbf\cdot s^2 / in^2}\)

Torsional stiffness (\(\hat{GJ}\))

\(24.31\times 10^6\ \mathrm{lbf\cdot in^2}\)

Flapwise bending stiffness (\(\hat{EI}_f\))

\(22.20\times 10^6\ \mathrm{lbf\cdot in^2}\)

Lead-lag bending stiffness (\(\hat{EI}_l\))

\(835.00\times 10^6\ \mathrm{lbf\cdot in^2}\)

Horizontal location of the shear center from the leading edge (\(\hat{SC}_2^{le}\))

\(-5.19\ \mathrm{in}\)

Horizontal location of the mass center from the leading edge (\(\hat{MC}_2^{le}\))

\(-6.01\ \mathrm{in}\)