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Zero Blade Deflection with Steady Wind

Wind turbine blades typically deflect during operation and this results in reduction in generated electrical power. We will use a steady wind field to examine the effect of blade deflection on generated electrical power.

Start-up

Double click on the Bladed icon to launch GH Bladed.

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File > Open Project > demo_a.prj

Wind

The demo project uses a pre-defined turbulence wind file. We will change the wind characteristic to steady. Click on to edit the wind characteristic. The default wind is set to 3D Turbulent Wind with a mean wind speed of 12 m/s. This turbulent wind is defined in the demo wind file. For our case, we will use a steady wind of 11 m/s. Change the option to No Variation and change the Wind speed to 11 m/s. Click on Apply to save the changes.

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Blade Modes

GH Bladed performs modal analysis based on the defined blade stiffness. The modes are used to predict blade deflection. Thus, we can eliminate the blade modes to simulate zero blade deflection. Double click on Modal Analysis.

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Change the number of blade modes to 0. Click OK to close the Modal Analysis Parameters window.

Simulation

We will run Start simulation because it simulates the start up response of a wind turbine. Highlight Start, and click on Run Now.

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Save the simulation result in the Bladed result folder (bladed 4.1\results). Name it startup_no_blade_deflection. Close the Calculation Progress window when the run is completed.

Results

We would like to compare the electrical power output of the demo wind turbine with and without blade deflection. The result for the case with blade deflection (blade mode unchanged) is provided below. Download and extract the files into the bladed result folder (bladed 4.1\results).

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Select "startup_no_blade_deflection" under Run Name. Select Summary information in Data Group. Select Electrical power for Variables. The electrical power will be plotted against time. Click on OK to finish data selection.

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Click on Channel 2 and select "demo_steady_wind_11" under Run Name. Select summary information and electrical power, as shown in the previous step.

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