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turbinesFoam / turbinesFoam

Actuator line modeling extension library for OpenFOAM.
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Allow turbine to rotate with a sinusoidal tip speed ratio #28

Closed petebachant closed 9 years ago

petebachant commented 9 years ago

Put amplitude and phase in dictionary. Of course it would be better to have a generator model, but this could suffice if the fluctuations are know a priori.

petebachant commented 9 years ago

Frequency should be equal to nBlades.

petebachant commented 9 years ago

Need to decide units of phase (degrees, radians, revolutions). If using radians

omega_ = meanOmega + omegaAmplitude*cos(nBlades_*(meanOmega*t - phaseRad));

where phaseRad is the angle of the first peak.

petebachant commented 9 years ago

Using radians for the phase may be a little difficult when trying to identify this angle from experimental data, since we may want to fit a cosine to an experimental time series of tsr versus angle, and angle is ever-so-slightly nonlinear with respect to time.

We should fit the experimental data with

tsr = mean_tsr + amp_tsr*cos(n_blades*(mean_tsr*t - phi_tsr))