Ambient vibration test of wind turbine blade in OWI-lab's Large Climate Chamber

Ambient vibration test of wind turbine of wind turbine blade in OWI-lab's Large Climate Chamber

Selected data from the large scale icing experiment as conducted in OWI-lab's large climate chamber on 15/11/2022. Results were presented during Eurodyn 2023 in :"Large scale test of vibration based icing detection for wind turbines", Weijtjens et.al. 

Data is (summarized, more details are given below):

- 24 Ten minute acceleration data files collected (MO04_acceleration_YYYYmmdd_HHMMSS.csv) 
- Pictures during the experiment timestamped (local time: UTC+1)
- Temperature measurements of the climate chamber's inflow temperatures
- Modal parameter results for X and Z direction 

All times are in UTC unless mentioned otherwise.

Measurement concept

The measurement data is collected during an experiment as conducted as part of the COOCK fighting icing  project led by Sirris. In the OWI-lab climate chamber a wind turbine blade was subjected to icing conditions. The test comprises the collection of ambient vibration data using three tri-axial accelerometers installed on the blade. During the day the blade is cooled and cold water is sprayed on the blade to simulate the growth of ice on the blade. The steps of the experiment are:

2022-11-15 10:04:00+00:00:	Start cooling to -10°C
2022-11-15 11:23:00+00:00:	Start spray
2022-11-15 12:13:00+00:00:	Accelerate spray
2022-11-15 12:49:00+00:00:	End of spray
2022-11-15 13:13:00+00:00:	Start heating
2022-11-15 14:14:00+00:00:	Start cooling to -10°C
2022-11-15 15:03:00+00:00:	Start spray
2022-11-15 15:43:00+00:00:	End of spray

For more information on the 

Ten minute acceleration data

Twentyfour ten minute samples of the 3 accelerometers on the blade sampled at 250Hz.  The data is two 2-hour blocks, one at night before the testing, the second 2 hour block is during the spraying.

The 10.1m long blade was instrumented with three tri-axial MEMS accelerometers (Micromega IAC-UHRS-Ud-03, ±3g) on the suction side of the blade. In which the X-direction corresponded to the edgewise motion of the blade, the Z-direction to the flapwise direction and the Y-direction to the less relevant lengthwise motion. The three sensors were installed at approximately 1/4, 5/8 of the blade length and 130cm from the tip of the blade.

Modal parameter data

The resulting modal parameter data ( for the entire day of testing) , in both X and Z direction are provided in MO04_mpe_*_20221115.csv. The data has following shape:

In which `mean_frequency` and `std_frequency` are the cluster mean frequency, are the cluster std. frequency and cluster std. damping and the cluster size (size). The LCSF algorithm is used. The algorithm used is described in Source.

Note: multiple rows share one timestamp, this is because the algorithm can detect multiple modes per timestamp.

Temperature data

The inflow air temperatures are shared in a separate .csv files: ClimateChamber_20221115.csv

Pictures

Picture are collected during the test are shared. Each picture is timestamped in local time (UTC+1)