UAE6 - Wind Tunnel Tests Data - UAE6 - Sequence K - Raw Data

**Overview**

Sequence K: Step AOA, Probes (P)

This sequence was designed to quantify the 3-D blade static angle-of-attack response in the
presence of rotational influences by varying the blade pitch angle. Sequence K used an upwind,
rigid turbine with a 0° cone angle. The wind speeds ranged from 6 m/s to 20 m/s, and data were
collected at yaw angles of 0° and 30°. The rotor rotated at 72 RPM. Blade and probe pressure
measurements were collected. The teeter dampers were replaced with rigid links, and these two
channels were flagged as not applicable by setting the measured values in the data file to
-99999.99 Nm. The teeter link load cell was pre-tensioned to 40,000 N.

The blade pitch angle ramped continuously at 0.18°/s over a wide range of increasing and
decreasing pitch angles. A step sequence was also performed. The blade pitch was stepped 5°, the
flow was allowed to stabilize, and the pitch angle was held for 8 seconds. Then the pitch angle step was repeated. Again, a wide range of pitch angles was obtained, both increasing and
decreasing. The file lengths for this sequence varied from 96 seconds to 6 minutes, depending on
the pitch angle range. Some short points were collected at 0° yaw and 3° pitch to verify the
functionality of the instrumentation. The file name convention used the initial letter K, followed
by two digits specifying wind speed, followed by two digits for yaw angle, followed by RU, RD,
or ST, followed by the repetition digit. The angle-of-attack motion was differentiated by RU
(ramp up), RD (ramp down), and ST (step down then step up). This sequence is related to
sequences L and R.

**Data Details**

File naming information can be found in the attached Word document "Sequence K Filename Key", copied from the Phase VI Test Report.