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direction and wind speed, it calculates the air density at each turbine, and the probability of the wind
coming from that direction at that wind speed for each turbine. It also calculates the wake losses due to
other turbines and modifies the wind speed at each turbine before entering that wind speed into the
power curve.
Openwind contains the following wake models. In addition, the user can run the energy capture with no
wake effects.

Park—this is the original Park model with a slight modification so that the wakes eventually
recover to the free-stream

Modified Park—this version of Park has been modified following the example of Garrad Hassan

Eddy-Viscosity—this wake model is a literal interpretation of the 1988 model published by
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Ainslie

Fast Eddy-Viscosity—this wake model is based on a solution by Dr. Mike Anderson

Deep Array Eddy-Viscosity Wake Model (DAWM Eddy-Viscosity) - this is a combination of the
standard Eddy-Viscosity model with a boundary layer wake model developed by AWS Truepower
based on a theory by Frandsen. More information is available in the DAWM white paper
available from here.

Deep Array Eddy-Viscosity Wake Model (DAWM Park Variant) - this is a combination of the
standard Park model with the DAWM.

Deep Array Fast Eddy-Viscosity Wake Model (DAWM Fast Eddy-Viscosity) - this is a combination
of the “Fast Eddy-Viscosity” model described above with the DAWM.
The Deep Array Wake Models (DAWM) are only available in the Enterprise version of Openwind. These
models are essential for estimating wake losses for utility-scale wind farms.
The Energy Capture settings can be accessed by going to the Settings menu and selecting Energy Capture.
Figure 3.1 shows the energy capture settings dialog.
There are two sets of energy capture settings. The top set is used during layout optimization. An
optimization runs thousands of energy capture calculations, and Openwind provides the option of running
an abbreviated energy capture that only covers the wind speeds over which the turbine is producing
significant power. The bottom set is used when calculating a full energy capture (also known as "Testing").
For the full energy capture, it is important to calculate across the entire range of wind speeds.
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OPENWIND USER MANUAL