For the aeroelastic pre-design of rotor blades a dedicated module is available.
With this module the aeroelastic performance of rotor blades can be determined
without the need for a full turbine model or a detailed blade design.
This makes it easy to scale up / down an existing blade design and modify it to
become the basis for a new blade design.
The Aeroelasticity I module can compute:
- Quasi-steady rotor characteristics
- Quasi-steady rotor loads (thrust, torque, blade root bending moment)
- Eigenmodes and frequencies (including dimensionless aerodynamic damping,
direction of the root bending moment, direction of the tip-vibration,
amplitude and angle of tip torsional moment)
- 'Once per rev' varying shape and damping of the rotor blades (including
span, flap-wise amplitude of the mode, lag-wise amplitude of the mode,
torsional deformation of the mode, blade chord length, aerodynamic damping
of the local section)
The Aeroelasticity I module can use either BEM or Vortex Wake model theory
as the basis for calculations. The models include torsional deformation and
transverse shear flexibility and many aerodynamic and structural dynamic coupling
terms for bending and torsion dynamics.
The noise emission module (requires Aeroelasticity I module) calculates the
sound power level of the wind turbine blades and sums it to the overall wind
turbine sound power level. For every blade element, trailing edge and inflow
noise sources are considered. The trailing edge noise source is calculated
from the model of Brooks, Pope and Marcolini. Inflow noise is due to the turbulence
in the oncoming flow, interacting with the blade. It is calculated from the
model of Amiet and Lowson. The noise sources are ('acoustically') summed
over the elements in order to obtain the total blade and turbine sound power
The output comes in the form of Power Watt Levels (PWL). The Overall PWL
(OAPWL) is specified per element to give an overview of the radial distribution
of the noise sources. A breakdown is given of the noise source types.
Download the FOCUS6 brochure (PDF) or contact us if you would like more information.