WF power curve - wake effect if turbine shut?

[julmou]

Hi

I find the WF power curve functionalities really interesting (Windfarm overview > WF power curve)

I was trying out the fact that we can deactivate a turbine or a turbine group, so that its wake effects are not taken into account in our WF power curve table.

This is a bit unrelated but I have a question regarding wakes:

if a turbine is not operating / shut-down, does it still have a wake on its neighor turbines or not? Is the wake caused only when the turbine is spinning? (or perhaps I am confusing with the wake turbulence). Thanks so much in advance.

[Morten]

It you deactivate a turbine site in the main WAT object hierarchy, it is treated as if it does not exist in the WF layout. 

You will also find some check boxes in the additional tree view next to the WF power curve. The production form deselected turbine sites does not contribute directly to the  WF power curve, but there is an indirect effect since their wakes affect the selected turbines. You can use it if you want to know the AEP a sub-group of turbines, while other turbine groups are still in operation.

The thrust-coefficient curve used in WAsP and WAT has a so-called static thrust coefficient (see the WAsP turbine editor), which is applied outside the wind-speed range of turbine operation, i.e. where the rotor is parked or idling. It is usually quite small and should not affect the AEP integrated over all wind conditions much.